GTA
All Springer/NP/PCP Air Gun Discussion General => European/Asian Air Gun Gates => China/Asian AirGun Gate => Topic started by: SagaciousKJB on June 28, 2017, 07:27:11 AM
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Well, I just wanted to share my experience doing my second tuning on an airgun ever. I got started with a B19 clone, and used Gene's guides, not to mention a lot of Roadworthy's patience :P Anyway, I've been putting off tuning up the Silver Kodiak for a long time, so long ago I bet the very helpful member that sent me the spare parts doesn't even remember sending them to me. But to him I'm very appreciative for that and all the information working on the Kodiak. This is one great community, and I'm sad that I only have the time to enjoy it and my air guns ever so often.
I want to run down just a basic history of the rifle. Kind of its "life story" I guess you could say. Sometime around late '14 or '15 I saw it on the shelf at Wally world, and I recognized it as a clone of a Beeman RS2--or so I thought--and the price was just right at an even $99.99; I had the cash, and I'd always wanted to try a springer, so I picked it up mostly on a whim. I'm glad I took it out to the local shooting hole, because it sure did diesel like crazy for what seemed like the first couple hundred shots. It sounded just like a rifle going off for the very first shots, and not just a .22 LR; I don't shoot a lot of powder burners, and it didn't make my ears ring, but hearing the echo of the sonic crack echo off the canyon walls made me think, "What did I buy here?" Never expected the recoil, and I swear it was actually more than my .22 LR.
Anyway, about 6 or 7 tins of 500 pellets later, it got got a lot more quiet. Maybe even too quiet, and it just kind of sounded like, "Doink!" every time it shot. It was still getting the job done, but I had the time and the parts, and it's been on my to-do list since last summer. It wasn't exactly giving me the best groups in the world, but I'd gotten pretty familiar with it, and could plink shotgun shells at 50 yards, using the included 4x32 scope it came with. Not too shabby, but the trigger really left a lot to be desired, and the scope-stop they screwed into the tube had gotten so messed up that the screw bent up, and stripped when I tried to remove it. To be honest I was kind of just curious to see what that kind of wear did on the inside. Which seems as good a transition for this picture as any...
You can see here all the debris from the machining had smashed into the face of the piston seal. I didn't get a picture of it, but the face of the compression chamber was basically imprinted with the outline of the seal and the screw that held it. I decided I'd need to polish that up.
(http://i.imgur.com/5u5QJZX.jpg)
Compression chamber after polishing it up:
http://i.imgur.com/KyMuN1P.jpg (http://i.imgur.com/KyMuN1P.jpg)
Basically what I did was I took a long wooden dowel I bought from a crafts store, and I then glued a piece of 220 grit sandpaper to it, and tore it off along the outline of the dowel so it had a flat face. Then, on the other side of the dowel, I drilled a pilot hole and then screw in a regularly phillips head wood screw. The pilot hole was to keep the dowel from expanding due to the screw being added, and then I could just use my drill with a phillips head to turn the dowel and polish the face of the compression chamber as it spins.
I did basically the same thing with the rest of the tube walls, but after having taped some sandpaper onto the the dowel. I accomplished this by first adding a layer of duct tape to the dowel and let it get kind of "ruffled", and then I turned the tape around and added another layer down the dowel with the sticky side facing outward. The first layer and its roughed texture ensured the outward facing layer wouldn't slip off the dowel as it turns and enters the compression tube, and then it was just a matter of wrapping the sandpaper around the tape and spinning the dowel with the screw head while slowly letting gravity pull it down; for the most part though, I just let it sit at the face of the compression chamber since that's where most of the slide runs on anyway. I left the sandpaper on the end of the dowel that the pistol seal strikes at 220 grit, but the walls of the tube I went up to 320 grit. There wasn't really a big reason for that other than I didn't want to glue on a new piece of 320 grit onto the end of the dowel... Yeah I know, but I didn't have glue and felt like this area was subject enough to as much abuse that a 320 grit finish would last long anyway. I'm relatively certain that whatever machining they used to make it in the factory was a lot more coarse than 220 grit, so it will be an improvement nonetheless.
(http://i.imgur.com/TrCPdiP.jpg)
Beyond that, I simply deburred a lot of the hard edges on the cocking slot and the opening for the trigger group. On my first tune job ever with a B19, I did this with needle files and that was a chore; a dremel made much easier work of this, but it still takes a while. They do seem to harden this steel a bit, so I used the diamond bits. Managed to only skate the compression tube surface once. Oh well, it doesn't need to be pretty.
(http://i.imgur.com/TrCPdiP.jpg)
(http://i.imgur.com/UgLl5FJ.jpg)
The piston itself needed a little TLC. Somehow, somewhere along the line, the cocking arm had left a deep gouge in the runner-slot for it. This just bothered the heck out of me, so I decided I'd give it a nice 320 grit finish, and put a lot of molly there, as well as deburr the edges of the cocking slot that were extremely rough.
(http://i.imgur.com/4hvbISl.jpg)
(http://i.imgur.com/LOCrZOg.jpg)
Beyond that, I sanded the face where the piston seal is seated with a 600 grit hone ( sorry forgot to take pictures ), and then polished this end of the piston that follows with a 320 grit sand paper. It's kind of interesting to me how much attention to detail was actually paid to this piston. That last inch of finer metal has an even smaller 1/4" band that is very flatly machined, but the overall majority of it is coarsely cut. Well mabe that's not so special, but this is only my second tune up job, I'm still interested to see the different parts.
(http://i.imgur.com/pAtdbGv.jpg)
I did add one little modification, and this was a very easy thing to do given that the Kodiak already had a screw for the stop. Well, it was a little more difficult for me given that I'd broken that screw off, but I decided that a big hole like my B19 had would serve well as a new scope stop. After all I wanted to put the new CenterPoint 4-16x40 scope that I got on there instead of the old combo-included 4x32--which to be honest served me really well and wasn't a bad scope in my eyes. But, again... Not every experienced here.
(http://i.imgur.com/Lw426d8.jpg)
Well, I didn't really want to do too much work to the barrel forks. They are held in by some interesting looking washers. They're a little hard to describe, but to make a long story short they'd broken in over time in such a way that I didn't really want to disturb the metal too much. However, there was some really nasty burrs present, and after I honed these down a little a really noticed the rough machining on this section. Up until now I'd been pretty pleased with the manufacturing quality of this rifle, but I could tell this is definitely where they were cutting corners. I suppose it makes sense, this level of cutting probably chews up more end-mills than other parts. I just decided to put a healthy coat of molly paste and call it good. But check out the size of that gouge... Yeesh.
(http://i.imgur.com/VNXEZdN.jpg)
Lastly, but certainly not least, is the trigger modifcation. So, basically, you can make a night and day difference with this trigger by removing exactly ONE c-clip, and a little piece of garbage they never should have included that looks like this...
(http://i.imgur.com/Q9GUSjK.jpg)
Okay, I don't know what the point of this thing was, I think some lawyer insist they add it, but essentially this is what makes this a "mock" 2-stage trigger. Now, I'll be honest.. I didn't figure this out myself, and I owe a lot of mention to another person (I'll mention them here later ) that really pulled this trigger group apart. In any case, the revelation is that it's really just a 1-stage trigger, and this little devil does nothing but add unnecessary pull tension on your trigger. Pop that sucker off and it's already a huge difference. Again I wasn't thinking of pictures before doing all this, so here is a picture of the trigger group with this piece removed. You'll notice the pin in the very lower left-hand portion of the trigger group on yours is missing from mine. There's also a set-screw and a spring there. Once you pop the C-clip and bolt holding it there off, take the screw and out and remove the spring, you're golden.
(http://i.imgur.com/bJCbjZE.jpg)
However, being the ambitious type, I bit off a little more than I could chew. I decided that in addition to some helpful hints posted by Dave99, I'd also polish the "intermediate sears". Nothing fancy, just a 600 grit finish. Couldn't hurt, right? Well, not sure what happened, I'll get to that later, but if you're going to mess with those be sure you don't leave ANY burrs on them. I'm just lucky I have a small background in machine tech otherwise I'd never thought to deburr them, but still if I hadn't touched them in the first place I wouldn't have the problem. The 600 grit finish really didn't do that much anyway; not as far as the pull tension amount is concerned, it just made the motion feel a little more glassy. Bottom line is I think I did more harm than good at this juncture, but removing the spring and that stupid tension fork is a no-brainer.
Okay well, the proof of workmanship is in the results right? Welll I hope not...
Let's start with the before.
(http://i.imgur.com/hGYvTBE.jpg)
Top two targets are from my Vantage, one using Crosman Premier Hollow Points on the left, and on the right using Crosman Premier Ultra Mags on the right. The bottom target is from the Kodiak post-tune, using Crosman Premier Hollow Points in .22.
Well, so here's where the problems with the trigger modification started. Everything was great at first, very smooth. Then, something started happening where it was getting stiffer and stiffer, and finally I couldn't even tell the difference between the safety being on or not at times. Anyway, as I said before, the solution ( other than not messing with them ) turned out to be deburring the sears, and I also added some molly paste for good measure.
Okay, well, so that should mean my groups tightened up a whole lot right? Wellllll... Just, no.
Here's 25 yards, something like 27 shots, and a 2" wide target. Well... At least it's zero'd, for a 4" group that is. Honestly I'm not sure if it's a rifle problem, a shooter problem, or a pellet problem. But I did manage to shoot this group at 15 yards. Which, I mean, I don't feel is anything to brag about, but I really wasn't grouping much better before. Eh, a tune-job can't fix lousy shooting I guess.
(http://i.imgur.com/rzDsJ8j.jpg)
However, I will say one thing... I have made a lot of creepy one-shot, one-bulls-eye shots with this thing since. It's almost like a hole-in-one shot in golf, except I've made at least three in the last few days. I didn't think to take pictures of the first few, just a fluke anyway right.... But this one, it was so perfect, and it has nothing to do with the tune-job or my marksmanship, but come on... 1 .22 pellet, 1 1/4" bulls-eye, and 1 shot... I know you guys find it as visually appealing as I do.
(http://i.imgur.com/pHuVJLc.jpg[img]
The one thing that's bothering me now, is this darn scope. The objective bell is SO close to the tube that these protruding portions sometimes come in contact when I adjust the objective. As you can see my solution was basically to try to file them down, but that was when it was on the Vantage. Now that it's on on the Kodiak, they're coming in to contact again, and so I have to get them sanded down. Which there was a faster way of doing this than a file, I think my dremel might be coming into play again.
Beyond that, I can't think of what else to do for a tube-up job. The barrel fork area, while rough, is solid and has no play so I think I'd rather just leave it. One modification I did was to the retaining pins for the trigger group and but-cap. Because of the knurled ends, you have to punch these out with a pin; well, not anymore, because I fixed them up in a drill bit and sanded them flat so now I can push them out with my fingers. Should make it easier to work on in the future.
I'm sure that I missed or over-looked some improvement that could have been made, but I think I did a pretty good job on the basic tune-up part. JM heavy tar on the part of the spring that goes into the piston, clear tar on the guides, molly paste on the piston and just on the edges of the seal. I also put some molly on the top hat, and sanded the ends of the springs to fit more flush. Just the basics covered in Charlie's guides.
Looking forward to getting re-adjusted to the trigger, and I think it's about all settled in now after a couple hundred shots, but I need to find some pellets it likes. Honestly, I think it could just be my own skill level preventing me from getting great groups with it, but as far as plinking goes I can hit some pretty small targets with it at ease.
[img]http://i.imgur.com/G9PPiqg.jpg)
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The one thing that's bothering me now, is this darn scope. The objective bell is SO close to the tube that these protruding portions sometimes come in contact when I adjust the objective. As you can see my solution was basically to try to file them down, but that was when it was on the Vantage. Now that it's on on the Kodiak, they're coming in to contact again, and so I have to get them sanded down. Which there was a faster way of doing this than a file, I think my dremel might be coming into play again.
Beyond that, I can't think of what else to do for a tube-up job. The barrel fork area, while rough, is solid and has no play so I think I'd rather just leave it. One modification I did was to the retaining pins for the trigger group and but-cap. Because of the knurled ends, you have to punch these out with a pin; well, not anymore, because I fixed them up in a drill bit and sanded them flat so now I can push them out with my fingers. Should make it easier to work on in the future.
I'm sure that I missed or over-looked some improvement that could have been made, but I think I did a pretty good job on the basic tune-up part. JM heavy tar on the part of the spring that goes into the piston, clear tar on the guides, molly paste on the piston and just on the edges of the seal. I also put some molly on the top hat, and sanded the ends of the springs to fit more flush. Just the basics covered in Charlie's guides.
Looking forward to getting re-adjusted to the trigger, and I think it's about all settled in now after a couple hundred shots, but I need to find some pellets it likes. Honestly, I think it could just be my own skill level preventing me from getting great groups with it, but as far as plinking goes I can hit some pretty small targets with it at ease.
(http://i.imgur.com/G9PPiqg.jpg)
Acknowledgements, thanks and links to resources I used:
Jeff aka Privateer for his awesome thread, help and the spare parts. This has everything you need to know about breaking down the Kodiak.
http://www.gatewaytoairguns.org/GTA/index.php?topic=64509.0 (http://www.gatewaytoairguns.org/GTA/index.php?topic=64509.0)
Dave99's write up on the trigger was totally indispensable, very thorough, and very appreciated. The diagrams and pictures made working on this trigger a breeze
https://www.gatewaytoairguns.org/GTA/index.php?topic=114058.msg1097361#msg1097361 (https://www.gatewaytoairguns.org/GTA/index.php?topic=114058.msg1097361#msg1097361)
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One modification I did was to the retaining pins for the trigger group and but-cap. Because of the knurled ends, you have to punch these out with a pin; well, not anymore, because I fixed them up in a drill bit and sanded them flat so now I can push them out with my fingers. Should make it easier to work on in the future.
LOL! Different strokes for different folks :)
I had been considering ADDING some MORE grip to those pins! Mine only needed a light tap to unseat. Bothered me to think that all the spring compression was held on those, and that if the wood wore on the stock in that spot, the pins could slip under full spring pressure. Even assembling, I liked having them gripped in place as I released the spring compressor to let the pre-load settle back on them. But I'm not very dextrous. If there are three parts to fit together, I can pretty much count on running out of fingers to keep everything aligned until it's all settled :)
Enjoy!
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One modification I did was to the retaining pins for the trigger group and but-cap. Because of the knurled ends, you have to punch these out with a pin; well, not anymore, because I fixed them up in a drill bit and sanded them flat so now I can push them out with my fingers. Should make it easier to work on in the future.
LOL! Different strokes for different folks :)
I had been considering ADDING some MORE grip to those pins! Mine only needed a light tap to unseat. Bothered me to think that all the spring compression was held on those, and that if the wood wore on the stock in that spot, the pins could slip under full spring pressure. Even assembling, I liked having them gripped in place as I released the spring compressor to let the pre-load settle back on them. But I'm not very dextrous. If there are three parts to fit together, I can pretty much count on running out of fingers to keep everything aligned until it's all settled :)
Enjoy!
Heh yeah I have to watch it now to make sure that I keep the tube up right or they can fall out of place, but I have the plastic stock and wasn't too worried about it wearing or letting them pop out. If I had to do it again I'd probably just sand the knurls down only a little bit. I just didn't like how hard to I had to hit them to punch them out, made it hard to figure out when the spring was or wasn't compressed enough to get them back in without peening them in with a hammer. I just frankly didn't want to try that, so sanding it was!
Honestly the biggest piece of trouble I had with this was getting the barrel back on. The pivot bushing in the barrel just didn't want to line up with the holes in the barrel forks UNLESS the barrel was at a 90 degree angle to the tube. Well, that's all fine and dandy, except that it's impossible to get the barrel at a 90 to the compression tube and then still put the cocking-mechanism into the slot. Then, if you leave the cocking arm in the slot, you can't bend the barrel to 90 without compressing the spring. So I did the stupidest thing, and compressed the spring down using an allen-wrench in the pivot, then quickly put the bolt in and closed the barrel. Crazily nerve-wracking and unsafe...
What I SHOULD have done ( and did the second time ) was I took the barrel out. That way I could clamp onto the front of the barrel housing without having to remove it or the cocking slot at all. So I lucked out that this was an interchangeable barrel. I really like this aspect of my B19 more, because it has the dual pivots on the linkage that allows you to pivot the barrel without compressing the spring. That's definitely something I'll have to keep in mind for future airgun tune ups.
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Just realized I didn't put the right pictures in! Here is a pic of the compression-chamber face where the seal sits, and the deburr of the trigger group slot.
I like the dowel-drill sanding tool. In the future I might attach the end to a saws-all and that way I can get a good cross-hatch. Buuuut for now elbow grease works fine for that.
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The one thing that's bothering me now, is this darn scope. The objective bell is SO close to the tube that these protruding portions sometimes come in contact when I adjust the objective.
Have you considered raising the scope by putting shim material like aluminum or plastic between the bottom mounts and the scope tube?
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The one thing that's bothering me now, is this darn scope. The objective bell is SO close to the tube that these protruding portions sometimes come in contact when I adjust the objective.
Have you considered raising the scope by putting shim material like aluminum or plastic between the bottom mounts and the scope tube?
Yeah I was thinking about that, but I wasn't really sure about how that would effect how well the rings were gripping the scope.
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Okay, well, today was interesting. I have bad news, and then I have some more bad news.
Well, so, worst things first... It bump fires. Past that, even after I set the adjustment screw to take out a lot of the creep, it seems to have just kind of.. Well, crept back in. Over a few hundred shots, it started having that familiar two-stage feel. Which I guess isn't such a bad thing, because I tested it for a bump fire again and it didn't happen, but tells me that the adjustment screw for travel needs some loc-tite on it. I'm going to take it down, measure how many threads are on the other side now, take the screw out, loc-tite it, and then turn it back in and get it to the same amount of threads. I'll have to fine-tune it again I'm sure, but at least then it won't change, and I should have found the sweet spot between dangerous and as short a pull this trigger can get.
Otherwise, it's still just grouping miserably. All these were at 25 yards, with .177 CPHP or CPUM, and .22 CPHP. I think I need to try something other than Crosman fodder, it's just kind of a waste of a tune-job. I'm just hoping that it is a problem with it not liking these pellets and not something else.
The best I could muster with .22... 3" targets, 1/4" bulls-eye
(http://i.imgur.com/9g9RA09.jpg)
The Ultra Mags before zero...
(http://i.imgur.com/AHFpCDZ.jpg)
The Ultra Mags after zero... (some misses not shown)
(http://i.imgur.com/QWGSKqQ.jpg)
The CPHP after zero'ing with the Ultra Mags...
(http://i.imgur.com/Q5JH6iZ.jpg)
SO yeah, I am thinking about trying some new pellets.
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The best I could muster with .22... 3" targets, 1/4" bulls-eye
In all seriousness Saga... that top bull isn't bad for a $98 Walmart gun at 25 yards.
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The best I could muster with .22... 3" targets, 1/4" bulls-eye
In all seriousness Saga... that top bull isn't bad for a $98 Walmart gun at 25 yards.
Yeah, I didn't think it was too bad, but it opened up pretty wide after just a few more shots. I just have a hunch it could be better with different pellets. Especially because just a few days before I made a sub-dime sized group with my Vantage NP, and I wouldn't expect that to be that much nicer of a gun.
If I could get half an inch I'd be happy.
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Try the RWS super domes
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Try the RWS super domes
Yeah I was thinking of trying those, as well as JSB and H&N. I really wanna give the Predator Polymags a try too since my 2100 loved them, but everything I've read says that the domed pellets do better for longer yard ranges.
I'm kinda torn between trying the H&N Hunting sampler packs, or trying their FTT and Baracuda pack. I can only find the FTT pack in .177 so I figure I'll just get to it later, because I really want to find something the .22 barrel likes.
These pellet prices sure add up quick though... Feel like I need to try one manufacturer's sample pack at a time. More costly in the long run, but otherwise I'm gonna be dumping $40-$50 into pellets, and I can't afford that sadly. One manufacturer's sample pack + shipping is gonna run me about $20.
Could be worse... Could be shooting a powder burner ;D
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This guy has got your back....
http://www.straightshooters.com/straight-shooters-full-pellet-sampler-.22.html (http://www.straightshooters.com/straight-shooters-full-pellet-sampler-.22.html)
* JSB GTO Lead Free 11.75 gr
* H&N Baracuda Green 12.65 gr
* Crosman Premier 14.30 gr
* JSB Exact Express 14.35 gr
* RWS SuperDome 14.50 gr
* Vortex Supreme 14.66 gr
* H&N Field Target Trophy (FTT) 14.66 gr
* Beeman Field Target Special Copper (FTS) 14.72 gr
* H&N Field Target Trophy (FTT) Power 14.66 gr
* JSB Exact 15.90 gr
* Air Arms Diabolo Field 16.00 gr
* Air Arms Diabolo Field Heavy 18.00 gr
* JSB Exact Heavy 18.13 gr
* H&N Baracuda Hunter Extreme 19.09 gr
* H&N Baracuda 21.14 gr
* H&N Baracuda Match 21.14 gr
* H&N Baracuda Power 21.14 gr
* Beeman Kodiak 21.14 gr
He also has 2 kits of 177 samplers as well ;)
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This guy has got your back....
http://www.straightshooters.com/straight-shooters-full-pellet-sampler-.22.html (http://www.straightshooters.com/straight-shooters-full-pellet-sampler-.22.html)
* JSB GTO Lead Free 11.75 gr
* H&N Baracuda Green 12.65 gr
* Crosman Premier 14.30 gr
* JSB Exact Express 14.35 gr
* RWS SuperDome 14.50 gr
* Vortex Supreme 14.66 gr
* H&N Field Target Trophy (FTT) 14.66 gr
* Beeman Field Target Special Copper (FTS) 14.72 gr
* H&N Field Target Trophy (FTT) Power 14.66 gr
* JSB Exact 15.90 gr
* Air Arms Diabolo Field 16.00 gr
* Air Arms Diabolo Field Heavy 18.00 gr
* JSB Exact Heavy 18.13 gr
* H&N Baracuda Hunter Extreme 19.09 gr
* H&N Baracuda 21.14 gr
* H&N Baracuda Match 21.14 gr
* H&N Baracuda Power 21.14 gr
* Beeman Kodiak 21.14 gr
He also has 2 kits of 177 samplers as well ;)
Yeah I was checking out that one first, but the shipping cost... Ouch. I only saw one of the .177 packs, but I could swear I saw one that was mostly hollowpoints?
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There used to be two in 177, now I only see one as well. :-\
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There used to be two in 177, now I only see one as well. :-\
Yeah, I thought I saw a hunter's pack of them long ago too.
That's one nice thing about the H&N sampler, they have the FTT and Baracuda, but also a hunting pack with hollow points and the Silver Arrow. I think for the ranges I want to shoot, though, I'm probably just better off sticking with domes anyway.
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As you try different pellets, be sure to clean the CP schmutz from the bore! Seems like the Chinese Beeman steel and Crosman pellet alloy are made for each other, with an unhealthy coating developing fairly quickly. And you've put quite a few Crosman's through the barrel.
I had looked at the pellet samplers quite a bit too. I ended up with the RWS based on tins of two types of Crosmans, another brand I can't remember, and the RWS superdomes. Nothing worked well until I cleaned the barrel. Then the RWS gave me tight enough groups that I stopped looking. I'm 100% certain that any remaining spread in groups is just the way I interact with the Beeman.
BTW: once the action is reasonable, the next tough part is the travel AFTER the full break. Another poster here has a good series of pictures on reducing this. Better follow-through is thoroughly demonstrated to equate with tighter groups. Here's the link: https://www.gatewaytoairguns.org/GTA/index.php?topic=64509.msg676471#msg676471 (https://www.gatewaytoairguns.org/GTA/index.php?topic=64509.msg676471#msg676471)
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Good to know about the gunk! I have put quite a few CPHPs through my barrels also, may be time for a good cleaning!
I also saw an interesting video on YouTube about sighting in both barrels and having them hold zero! I thought this would be impossible till I saw this guys solution! Yep, he suggested a second scope! Sight both in to their own barrel and just swap barrel and scope at the same time when going to a different caliber! He claims the scope stop ensures scope placement at the exact same spot which will maintain zero! Simply Genius!
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As you try different pellets, be sure to clean the CP schmutz from the bore! Seems like the Chinese Beeman steel and Crosman pellet alloy are made for each other, with an unhealthy coating developing fairly quickly. And you've put quite a few Crosman's through the barrel.
I had looked at the pellet samplers quite a bit too. I ended up with the RWS based on tins of two types of Crosmans, another brand I can't remember, and the RWS superdomes. Nothing worked well until I cleaned the barrel. Then the RWS gave me tight enough groups that I stopped looking. I'm 100% certain that any remaining spread in groups is just the way I interact with the Beeman.
BTW: once the action is reasonable, the next tough part is the travel AFTER the full break. Another poster here has a good series of pictures on reducing this. Better follow-through is thoroughly demonstrated to equate with tighter groups. Here's the link: https://www.gatewaytoairguns.org/GTA/index.php?topic=64509.msg676471#msg676471 (https://www.gatewaytoairguns.org/GTA/index.php?topic=64509.msg676471#msg676471)
Good point! I didn't even think about cleaning the barrel. I need to go pick up some more Otis patches. I don't think I've ever cleaned the barrels. Closest to it is putting a coat of oil in them for winter storage.
I noticed that screw as well and wasn't really sure what it was for. It just stops the trigger from over-traveling? Looks easy enough, I just gotta get a tap and a screw. Thankfully there's a place in town I should be able to buy them just the screw, drill and tap instead of having to buy a whole set. Then again, I always wanted a tap and die set.... This is where my money goes :P
PaulT58,
Yeah I thought about doing that too actually! I use markers to mark where my scope mounts are, and then I take a machinist's scribe and mark the very edge of the mounts so I know exactly where they were on the rail. The zero does hold pretty well!
My solution was going to be to zero in with the .177, and then note where the scope settings are on my turrets and swap to the .22. Then I'd zero it, write the turret numbers again, and that way I'd know roughly how much to adjust whenever I switch from one barrel to the other.
The only problem is that it doesn't seem to really hold zero very well even when you take out the barrel and put the same barrel back in. That set screw has to be torqued down TIGHT and I think to have consistency it'd be best to tighten with a torque wrench.
Oh also Dave, you were right about that travel-adjustment being one dangerous little guy. I've been trying to take it up just to the point where it would bump fire and then back it off. I was testing last night, cocked it, and didn't even get the barrel closed before "BANG!" and I had to clean my drawers.
So I have it backed off pretty good now, making sure it won't bump fire with a hefty whack on the butt stock with a rubber mallet. It's not nearly as short a pull, but I feel better about the safety of it.
Kind of disappointed I've already went through 2 dry-fires since this tune-up :/ That's gotta be bad for the seal...
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Oh also Dave, you were right about that travel-adjustment being one dangerous little guy. I've been trying to take it up just to the point where it would bump fire and then back it off. I was testing last night, cocked it, and didn't even get the barrel closed before "BANG!" and I had to clean my drawers.
So I have it backed off pretty good now, making sure it won't bump fire with a hefty whack on the butt stock with a rubber mallet. It's not nearly as short a pull, but I feel better about the safety of it.
Kind of disappointed I've already went through 2 dry-fires since this tune-up :/ That's gotta be bad for the seal...
Glad you got away from the bump firing! Any way you can do that with a pellet in the chamber? Maybe a good pellet trap fairly near the muzzle, with the rifle on bags, whacking the shoulder area with a mallet?
BTW: remember on this model, if you pull the trigger part way, even if you CAN push it back and reset the safety, the sear position doesn't change, and bump fire risk goes up... once you start to pull the trigger either go all the way on target, or finish shooting the round into the dirt or other non-ricochet/shot damage direction.
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Oh also Dave, you were right about that travel-adjustment being one dangerous little guy. I've been trying to take it up just to the point where it would bump fire and then back it off. I was testing last night, cocked it, and didn't even get the barrel closed before "BANG!" and I had to clean my drawers.
So I have it backed off pretty good now, making sure it won't bump fire with a hefty whack on the butt stock with a rubber mallet. It's not nearly as short a pull, but I feel better about the safety of it.
Kind of disappointed I've already went through 2 dry-fires since this tune-up :/ That's gotta be bad for the seal...
Glad you got away from the bump firing! Any way you can do that with a pellet in the chamber? Maybe a good pellet trap fairly near the muzzle, with the rifle on bags, whacking the shoulder area with a mallet?
BTW: remember on this model, if you pull the trigger part way, even if you CAN push it back and reset the safety, the sear position doesn't change, and bump fire risk goes up... once you start to pull the trigger either go all the way on target, or finish shooting the round into the dirt or other non-ricochet/shot damage direction.
Yeah I'm not sure if I bumped the trigger or not actually. I was loading a pellet into it, and had a plywood trap setup for the bump fires. Otherwise I was firing into the same rubber mallet--catches the pellets quite well. Anyway, I would hold on to the barrel and wrist of the rifle, cock, wedge the stock between my couch arm and my leg, hold on to the barrel, load the pellet, grab the wrist, and then pinch and angle the muzzle at the plywood board and swing the stock through to close the barrel while keeping the muzzle pointed at the plywood. For whatever reason, right before I locked the breech up, it fired and the jet of air was so hard it knocked the breech seal off the barrel, and hit my fingers with a jet of air so hard I'd thought the pellet just barely missed them. Turns out it hadn't even closed or fired the pellet.
Highlights the dangers of working on these sears pretty well, glad I was paying attention to how I was holding the rifle, but jeez it was still surprising. I'm not sure if I bumped the trigger with the safety on, or if it the over-lap between the two sears was just two small. I usually finger-test it with a flat-head screw-driver first. I set the adjustment until I can see the overlap of the two sears is small, then I use a small flat-head to push the main sear down on top of it, and just kind of pry on it with my fingers. A lot of the times even with a sear engagement of 1/32" or more, you can still push the sear down enough to disengage.
I think this is due to the nature of the sear geometry itself, because there's a kind of "slope" at the very rear of it. I believe that slope is actually what gives it the pseudo 2-stage feel. Because when you pull the trigger, the portion of the bottom sear that begins to slope is pressing against the flat of the top main sear, so as it travels it pushes up on it just the slightest as those two surfaces which were once parallel become angled. It feels a bit like the main sear is traveling over a "hump", by nature of it moving in a concentric path, even though it's really just a dropping slope. So once it feels as if the trigger as traveled over this "hump" during the trigger break, that's when the edge of the top sear is on the downward slope.
The only real safe way to take up the travel safely would be to re-profile the sear and make this downward slope shorter. That's a pretty ambitious endeavor in my opinion. I'm pretty good with tool-making and metalworking with my hands, and fine stuff like this, but I don't think I'd be comfortable doing that after you pointed out they only case harden these.
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After reading your comment about the ramp on the sear, I looked at my pictures again, including the hi-res originals (still with the markings.) I saw what MIGHT be an upslope on the intermediate sear, aiming up at the end. More prominent in my eye, though, is the detail on how these are stamped. The stamping/cutting deformation rounds BOTH sear pars right near this critical spot. Any lateral play in these levers will allow them to engage more, or less, securely, even with the trigger screw setting in my photos.
I was interested to note that the intermediate sear has a DEFINITE downslope toward the front of the rifle starting behind that last engagement point. With longer trigger travel this WOULD give the illusion of two stages, assuming the front part ramps the other way.
While looking at the pictures I realized that, for this rifle, it's important to check bump fire from the butt of the stock AND from the top. The intermediate has enough mass hanging toward the rear that a whack over the breech needs to be protected against. Dropping the rifle so it lands on the scope would be one way to cause this kind of bump fire. The snap of the barrel against the locking ball would be another. I suspect the second is what happened to you.
Glad you did not get hurt!
Boy, I wish Beeman had left that other trigger model on these things!!!!!
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After reading your comment about the ramp on the sear, I looked at my pictures again, including the hi-res originals (still with the markings.) I saw what MIGHT be an upslope on the intermediate sear, aiming up at the end. More prominent in my eye, though, is the detail on how these are stamped. The stamping/cutting deformation rounds BOTH sear pars right near this critical spot. Any lateral play in these levers will allow them to engage more, or less, securely, even with the trigger screw setting in my photos.
I was interested to note that the intermediate sear has a DEFINITE downslope toward the front of the rifle starting behind that last engagement point. With longer trigger travel this WOULD give the illusion of two stages, assuming the front part ramps the other way.
While looking at the pictures I realized that, for this rifle, it's important to check bump fire from the butt of the stock AND from the top. The intermediate has enough mass hanging toward the rear that a whack over the breech needs to be protected against. Dropping the rifle so it lands on the scope would be one way to cause this kind of bump fire. The snap of the barrel against the locking ball would be another. I suspect the second is what happened to you.
Glad you did not get hurt!
Boy, I wish Beeman had left that other trigger model on these things!!!!!
Yeah it's kind of interesting how close it is to the trigger group in my Vantage, which I guess is a B19/Gamo 440 clone that has never really been renowned for having a great trigger. So that makes you wonder why they copied a bad trigger... At least the Vantage has a nicer feeling blade.
I finally bit the bullet (ha pun) and bought the Straight Shooter's .22 caliber pellet sampler. That was a hard $50 to spend, especially if it just turns out I not so good at shooting any kind of pellet. I wanna try to find something to use .22 before the .177 though.
Kodiak, just trying to get a zero, with the CenterPoint 4-16x40 AO turned down to 4x and using Crosman Premier 10.5gn:
(http://i.imgur.com/juSQFIO.jpg)
It WANTS to group, but at the moment the best I can seem to muster with these pellets is minute-of-tincan at 25 yards, and even then the odd flyer goes so wide as to miss even that.
My Vantage seems to like the CPHP and the CPUM pretty well, so I think I'm just going to save them for that and then wait on the .22 sampler to get here to break out the Kodiak again. I just wanted to get a feel for the trigger today, and I'm pretty happy with it. Feels nicer than the Vantage's, and it's a night and day difference between stock. I can actually hold my breath and get through the trigger break without dying of asphyxiation now.
Still, I'm kind of disappointed... I got this Vantage out of the pawnshop and put a lot of work into it and bought it the expensive ( for me ) scope thinking I could make it a tack-driver, yet I'd consistently make more shots with the Kodiak time after time. SO then I swap out the nicer scope onto the Kodiak, and the "cheapo" scope onto the Vantage, and now I'm shooting better with the Vantage! I suppose I could blame the scope, but I figure I better try some new pellets before I go down THAT rabbit hole.
I just have a hunch once I find it the pellet that it likes, it will start to shine. Crossing my fingers it will find something it likes in .22 because the vantage is already such a nice .177 gun.
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Be patient. Kenny Kormandy at his my airgun reviews on Youtube, reviewed the Crosman Crusher. It was a pretty ho hum grouper. Then he found the magic pellet and shot his best recorded group ever with that Crusher.
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Be patient. Kenny Kormandy at his my airgun reviews on Youtube, reviewed the Crosman Crusher. It was a pretty ho hum grouper. Then he found the magic pellet and shot his best recorded group ever with that Crusher.
That's what I'm hoping for! Unfortunately it looks like it's gonna be a while longer, I screwed up typing my address for Straight Shooters.
Also I ran into ANOTHER problem... Not sure how much of a headache this will be, but one of my stock-screws ( right side of the rifle by the barrel forks ) has the hex-socket stripped out. :/ So next time I take it down I'm gonna have to figure out how to get it out of there under as much torque as I put in it, and then also to replace it. Yay gorilla arms!
Looks like this place has me covered...
http://www.@#$%^.com/Stock-Screw-Kit-for-Beeman-Sportsman-Series-p/beemanstockscrews.htm (http://www.@#$%^.com/Stock-Screw-Kit-for-Beeman-Sportsman-Series-p/beemanstockscrews.htm)
Alternatively, I'm just going to take the left one out, go down to Tacoma screw, size and match it and also pick up a screw-extractor kit. I have one of those little EZ-out screw extractors, but it has literally never worked, and for screws torqued out far less.
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Do you live near Seattle/Tacoma?
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Do you live near Seattle/Tacoma?
Not very close, it's just kind of a regional thing since I'm in the PNW
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I'm going to have to put this little project on a slight hiatus, ran out of playing funds for the month. My SS pellet sampler is going to come in, and I won't have money for zero'ing fodder or patches to clean the barrel, so I think I will be putting this on hiatus for a few weeks. Besides I think I need to open it up and check things out on the inside, I was doing some "chronograph" testing today and noticed something grinding during the cocking-cycle. Uh-oh
The chronograph results were not bad, though I'm using an app for my android that uses sound to measure, so I'm not sure how accurate it really is. I've heard people say it's within 10% of their actual chronograph figures as long as it's setup right. You have to know the distance between the muzzle and your target, the distance of the device to the muzzle, and the distance of the device from the path of the pellet... There's also a "de-bounce" effect that you can play with because some guns make extra noise after they fire and this will lead to some "hot" rounds left in the result as it is picking up the sound between muzzle blast and piston-slap.
Anyway, it's shooting pretty close to advertised with the CPHP at 7.9 gn, but I don't like how low those numbers are with the 10.5 gn. I want to be pulling 700 FPS with 14.3 gn in .22, so to see it that close only at 10.5 gn is a little disappointing. Again, though, not sure how accurate this app is, and of course it could change pretty with the barrel size since that makes pressure difference. I'm not really sure the drop in velocity from 908 fps to 711 fps is inline with an increase in projectile weight from 7.9 to 10.5 gn, and the heavies feel tighter in the barrel to me than the CPHP.
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Just a thought...
I find usually the cheap-o allen wrench they send with items is more the culprit than the actual screw stripping.
I bet if you pick up a new quality metric allen wrench set, even if the screw has rounded corners, it will engage the screw better and you will be able to get it out.
Extractors (easy-outs) usually fail on hardened socket head cap screws. If the screw head really is FUBAR you may be able to find a "standard" size wrench that is a tad larger than the metric one and tap in with a hammer enough to get the old screw out.
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Here are the numbers I got when I tested mine for comparison. These are the average of 5 shot strings:
.22:
H&N Sniper Magnum 18.00gr 622.66
Crosman Hollow Pt 14.30gr 707.20
JSB Exact Jumbo 18.30gr 624.86
Gamo TS-22 22.00gr 560.36
.177:
H&N Field Target 8.64gr 908.96
JSB Exact RS 7.33gr 931.88
H&N Sniper Med 8.50gr 927.60
Benj Hollow Point 7.90gr 962.86
I also did the trigger mod where you remove the loop spring from the little teeter thingy, It did make a pretty significant difference!
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Thought I'd mention that Beeman has a new model. It's a dual caliber air rifle with a wood stock, gas piston, and in the silver finish like your Beeman's are. Here it is:
https://www.amazon.com/gp/product/B01FEE43EK/ref=ox_sc_act_title_2?smid=ATVPDKIKX0DER&psc=1 (https://www.amazon.com/gp/product/B01FEE43EK/ref=ox_sc_act_title_2?smid=ATVPDKIKX0DER&psc=1)
Notice there are zero reviews so far. I would not mind picking up one of these. The silver finish, hopefully, is more rust resistant than blue finishes. Here, rust is a constant enemy.
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I almost bought that one because I couldn't find the Silver Kodiak with the black synthetic stock for less than $150. Then I found one at Wally World for $99! That is an excellent price for that with a wood stock! Essentially the same rifle, just in wood.
I was wanting the black/silver scheme and if I had gotten the wood stock version thought about refinishing the stock to a really dark, blackish grey color that would probably look awesome with the silver!
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I almost bought that one because I couldn't find the Silver Kodiak with the black synthetic stock for less than $150. Then I found one at Wally World for $99! That is an excellent price for that with a wood stock! Essentially the same rifle, just in wood.
I was wanting the black/silver scheme and if I had gotten the wood stock version thought about refinishing the stock to a really dark, blackish grey color that would probably look awesome with the silver!
It looks like that one has a gas ram instead of a spring!
Paul,
My numbers are pretty close to that in .177, but in .22 I'm only getting 711 out of a 10 grain pellet. I think since it works based on sound that maybe it just couldn't pickup the 10.5 grain as well as the 7.9 grain. I was really just wanting some figures to jot into ChairGun and to see if it was doing okay and I think it's pretty close.
Hoosier Daddy,
Yeah unfortunately I tried it with one of my good bits... Well, I don't know how "good" it is, but it was part of a Black and Decker bit set, so seemed a little harder than the average. I was also thinking about a slightly over-sized one as well.
The steel on it seemed kinda of soft to me, but the bit might have just been harder. It's got enough metal in there now that the right sized torx bit might be able to grab on too.
I'm not TOO worried about getting it out, I know that worse things come to worse I can either...
1. Cut a slot in it with a cut off wheel ( would involve cutting the stock some )
2. Tap the cap with some left-handed threads and turn it out with a new screw ( takes specialized tools that might cost a bit )
Number 1 would be quick, dirty and cheap but I wouldn't even need to buy a new screw! Just don't want to have to cut the slot into the stock that would need to happen as well since the screw is so far below the surface. Might be a little tricky cutting.
birdmove,
You should check out something called eezox. A lot of gun owners in rusty environments love it.
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Well, the GrabIt got it! First time this thing has ever worked. I think the trick is to forego the drill once you start trying to grab at it with the tap-side. I'm probably going to cut a slot into it with a dremel so I an use a flat-head with it until I get it replaced. I don't know that I'm going to buy that $10 screw kit though versus just going down to a hardware store and matching it. They don't seem like real special lengths or anything.
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Good job!
A decent Hardware store should have it. Button head in a metric sockect head cap screw.
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Yes, that new Beeman I showed with the Amazon website is a gas powered break barrel. They are starting to make that switch over.
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Yes, that new Beeman I showed with the Amazon website is a gas powered break barrel. They are starting to make that switch over.
Having a very limited experience, I have to say that I prefer gas pistons so far. There's something about the shot cycle of the Vantage that just feels much nicer, and they seem to supply a bit more power. Not to mention I didn't really "enjoy" tarring the main spring, could do without that experience again. I think people usually advocate for springs because they're easier to replace when they break though.
Speaking of springs, how do you tell when one is worn out? Mine was still pretty straight, so I just put it back in and kept using it, but I wonder if there's some fatigue going on that's keeping it form being as powerful as a new spring could be?
I also notice the pre-load on mine wasn't anywhere near as far out of the cylinder as it was for Jeff's rebuild. The back of the washer on the spring guide was actually just inside of the cylinder for me, whereas in his rebuild pics, you can see it sticking out an inch or so. I guess I should have measure my spring to make sure it was as long as it should have been, maybe it's been "compacted"?
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Had a good day shooting yesterday. I got a tin of 175 Crosman Premier pointed 14.3 grain .22s to sight in with before I started trying pellets from the Straight Shooter's sampler. At the end of the day, I found that the Air Arms and JSB varieties did well, but also discovered that it likes the Crosman Premier pointed ones pretty well too.
I know most people would scoff at these groups, but keep in mind I don't shoot supported on a bench or sticks so I think it's pretty good. All groups are at 24 yards... Why 24? Well, because I was 3 feet short of being able to do 25. I think the Air Arms pellets performed the best, but from group-to-group I think I need to get onto a bench to really measure out accuracy differences between all these.
Pretty sad that all the Beeman and H&N pellets did so poorly, I was really wanting to use the Barracuda Hunter Extreme. However, I don't think that the standard pellets are lacking stopping power, because wouldn't you know it one of the cotton-tails that is eating from my garden popped out. I took it with a heart/lung shot at 20 yards with the Crosman Premier pointed, and could not find any trace of an exit wound.
I'm not really sure how much I should trust these chronograph results from Chronoconnect... They say that it can be accurate within "10%", and I've compared my numbers to other results I've seen here and they're about 8% slower... I guess they seem reasonably close, but going by Chairgun, the drop at 50 yards doesn't seem as bad as it says. Seems to only be 2-3 inches of drop versus the 5-6 Chairgun claims, but if I try to jot different velocities in to match that POI, I get velocities that seem way out of range.
First I measured with the 14.3 gn Pointed Premiers
(http://i.imgur.com/80DWQsY.png)
Second were the 11.6 gn GTO lead free JSB, which I expected to be going much faster weighing so much less
(http://i.imgur.com/avrM0De.png)
JSB Heavy
(http://i.imgur.com/S0GYyyO.png)
JSB Express ( ignore the Exact 13 gn measure and ft lbs)
(http://i.imgur.com/er5Wsuu.png)
Barracudas
(http://i.imgur.com/qDtLoOB.png)
Air Arms 16 gn
(http://i.imgur.com/PxTMdXw.png)
Air Arms 18 gn (accidentally left it as JSB Heavy)
(http://i.imgur.com/S0GYyyO.png)
The Straight Shooter's pack labelled in order of the ones I tried...
(http://i.imgur.com/94hVHtX.jpg)
(http://i.imgur.com/btPcRA7.jpg)
(http://i.imgur.com/YM3eUF6.jpg)
(http://i.imgur.com/7E7xVhu.jpg)
(http://i.imgur.com/QKWH80R.jpg)
(http://i.imgur.com/eHVWgsg.jpg)
This was the best group of the day... Hard to tell, but there were 3 shots in the middle there.
(http://i.imgur.com/broP8pu.jpg)
Here is a set of groups going from the lighest JSB to heaviest ( in the center ) and the two Air Arms, lightest to heaviest.
(http://i.imgur.com/qum8zUq.jpg)
So yeah, I'm pretty much narrowed down to these pellets that will group "reasonably" well...
JSB Express
JSB Exact
JSB Exact Heavy
Air Arms Field Diablo 16 gn
Air Arms Field Diablo 18 gn
Crosman Premier Pointed
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I shot some more groups today, and I think I am just not good st shooting groups. I need a bench or some shooting sticks, otherwise I can't really tell the difference between a jerked trigger and a flyer. So I decided to shoot 10-11 shot groups to get a better idea of how these are grouping.
From top to bottom
Crosman Premier Pointed 14.3
AA Field and JSB Exact 15.9
AA Field Heavy and JSB Exact Heavy 18.14
(http://i.imgur.com/flF8chy.jpg)
But beyond my lousy group shooting, I am nailing bottle caps at all set ranges. Very happy with the accuracy now, I am pretty sure the shooter is the limiting factor now.
I am also extremely pleased with how well the Crosman Premier Pointed shoot. Pretty surprising given how lousy the domes and hollow points shot. In the meantime the 18 grain JSB seem to group pretty tight too, barring a few odd flyers. Too bad their poi is down/right from the cheap Crosman fodder. I have a feeling that I could have got the 16 grain tighter.
The trigger is much better now but I do still have some problem getting it to break before I run out of breath.
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It looks to me like your best results are from the pellets that have the highest energy shown in your chrony-like device.
One of my pet theories is that a dome behave better than a pointed pellet because it destabilizes more slowly. If the point is not exact dead center as the bullet spins out of the barrel, air will help it wobble more the farther it goes. Just a theory.
the second photo leads me to believe you might like results from the RWS Superdomes. The weight is very similar, and the domes are quite friendly.
And the photos DO suggest that there is something going on with your hold and/or trigger pull. I suspect long travel before break added to long travel AFTER break is pulling things off. I am almost inspired to try the after-break travel screw on my Beeman now :)
I think your idea of some sort of bench testing is good, especially if the challenge is trigger technique. My Beeman does not mind having the forestock resting on a fluffy, slippler fleece or (even better) wool pad. It HATES sitting on anything that restricts its movement.
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I know most people would scoff at these groups, but keep in mind I don't shoot supported on a bench or sticks so I think it's pretty good.
Wait... you mean you are getting those kind of groups OFF-HAND? Out at 24 yds
Those 3" Shoot-N-C bulls are pretty small at that range.
Dang Man, that IS pretty darn good!
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I know most people would scoff at these groups, but keep in mind I don't shoot supported on a bench or sticks so I think it's pretty good.
Wait... you mean you are getting those kind of groups OFF-HAND? Out at 24 yds
Those 3" Shoot-N-C bulls are pretty small at that range.
Dang Man, that IS pretty darn good!
Thanks, I needed to hear that lol. Yeah I sit on my porch with my knee propping up my elbow, but it really doesn't add as much higher stability as you'd think with this big 11 pound gun, I still wobble a lot. The 16x setting on my scope helps me see, anything less than 4 and I wouldn't be able to.
Dave99, yeah I was thinking about getting some shooting sticks and hoping the ability for the stick to travel forward and backward will compensate kind of like the paint roller trick does for benched shooting. I know nced shoots off a bucket and sticks, and he does a pretty good job.
Unfortunately it hated the Superdomes. But the JSB Express have the same weight as these Crosman and I shot a pretty good group with them too.
The 18 grain ones did a fine little group too, just the poi was off. I think I'll probably get the JSB Express, the air arms and more Crosman and then figure out a way to bench up before testing again. Eventually I wanna do some testing at 50 yards too, but I gotta go out to the local shooting hole. Only 50 yards shots I have here are beyond a field of brush, trash and barbed wire... yikes.
I think I'm gonna try one of those over-travel screws as well Dave99. I think the lock time is so long that jerking after the break definitely effects it, and I have found myself training bad habits into that because instead of letting the trigger break right when the reticle is still, sometimes the reticle is still moving and I have found myself kind of flinging it to the point of aim I want in the last split second.
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(http://i.imgur.com/n1CAPyf.jpg)
So in lieu of buying a whole tap and die set, or over-spending on just one tap or die and a wrench, I just decided to approach the over-travel stop in a different way. Happened to have some wire/rod that I knew to be almost the same diameter of a small drill bit. Still haven't actually measured it, I'm guessing it's 1/16". Anyway, it was kind of tricky marking where the hole should be drilled, and the first one was pretty low. It doesn't seem like it would make that much of a difference being so close, but because of the angle, the tip of the trigger still had a lot of over-travel.
Not really as much adjustment as possible with a screw, but on the other hand if I need to adjust it, it's pretty simple. If I need more travel, I can just grind a little bit on the trigger group housing, and if things go bad I can use JB weld to fill in the gaps.
Speaking of JB weld, had to use that to fix the pin in, so I haven't really had a chance to test fire it yet except with the stock off and that was pretty tricky, and doesn't really give me a good feel. I'm sure there's still a minute amount of over-travel, but like I said I can add JB weld later, then sand it down to tune it out further. Sounds kind of like a pain, but I have a reason...
Basically, once it's set, it's set. This stopping point being static means that if in the future my travel-length adjustment screw gets loose or changes, this is kind of a reference point because if the travel screw isn't set right, then the trigger won't be able to move far enough back to break. No need to remember how many turns or some other way of recalling the travel-adjustment setting, this kind of locks it in.
Plus, if I overlooked something real bone-headed, pretty easy to undo with my dremel and a cut-off wheel. Speaking of which, made some new stock screws after I confused inch/lbs with ft/lbs of torque...
(http://i.imgur.com/oOulLGz.jpg)
I'll have some chronograph numbers soon I hope. Also getting a shooting stick, or somehow making some of my own, so I can really see which of these pellets groups best. I was thinking I could just make my own, but then I saw some on WM online for about $10 that seem like they'd work better anyway--think it'd be worth the money. I'm only cheaping out on every other aspect of this :P
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Well, I'm really not sure if I'll be able to get very tight groups with this rifle. Tried a shooting stick, and it's still all over on the horizontal spread. I wonder if there's too much barrel play, but I've got to wrench it quite a bit to feel any wiggle.
The trigger is bugging me, because it is such an ultra-light pull when I apply molly paste to it. However, it seems once it wears down, it starts to creep back up with pull force. I am thinking that I need to get some fine grit sand paper and put a really nice polish on the sears to mimic that molly paste permanently. The springs are very light, it's all the finish in the sears. I probably made a mistake in the direction I was polishing with the 600 grit, as I was going side-to-side on the sear faces instead of from front-to-back, which is the direction they travel when rubbing against each other. SO long story short, my sears are rubbing against the grain of the finish.
Should be getting my chornograph in the mail tomorrow to put up some velocity figures. Interested to see how close they compare to my ChronoConnect figures.
(http://i.imgur.com/35DFnmb.jpg)
(http://i.imgur.com/ES4rJ9z.jpg)
There's lots and lots of flyers, but the actual groupings are about as tight as anything else I've mustered. Still not really getting that reticle real still either so it's not like lousy shooting can be ruled out.
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Well, looks like it's a whole new beast in a bad way...
Top velocity I've reached testing with the new chronograph is 612 FPS with 14.3gn Crosman pellets. It should be sitting closer to 700 from other member's results I've seen, though those weren't from rifles that were "broken" in.
I think I might have put too much tar on the spring and maybe enough molly paste on the seal. Suppose I'll break it down and re-lube it to make sure.
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Well, looks like it's a whole new beast in a bad way...
Top velocity I've reached testing with the new chronograph is 612 FPS with 14.3gn Crosman pellets. It should be sitting closer to 700 from other member's results I've seen, though those weren't from rifles that were "broken" in.
I think I might have put too much tar on the spring and maybe enough molly paste on the seal. Suppose I'll break it down and re-lube it to make sure.
I've currently got a Beeman sportsman series gun apart and although it has the RS3 trigger, the internals seem pretty similar to yours. I'm having trouble getting the barrel back on during reassembly - I was wondering how you did it? I can't seem to get the pivot bolt to be able to go through the fork and breech block - it's like they aren't aligned properly.
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Well, looks like it's a whole new beast in a bad way...
Top velocity I've reached testing with the new chronograph is 612 FPS with 14.3gn Crosman pellets. It should be sitting closer to 700 from other member's results I've seen, though those weren't from rifles that were "broken" in.
I think I might have put too much tar on the spring and maybe enough molly paste on the seal. Suppose I'll break it down and re-lube it to make sure.
I've currently got a Beeman sportsman series gun apart and although it has the RS3 trigger, the internals seem pretty similar to yours. I'm having trouble getting the barrel back on during reassembly - I was wondering how you did it? I can't seem to get the pivot bolt to be able to go through the fork and breech block - it's like they aren't aligned properly.
It would have been REALLY hard for Beeman to spring that part to put the pin in if it had been misaligned. Perhaps you could try checking the alignment WITHOUT the anti-beartrap connected? If that looks OK then the challenge is jiggling all those parts just right so they get to the "sweet spot" where the hinge bolt can be put in.
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You're probably trying to put the barrel straight in. Can't do that. It has to go in at an angle to the compression tube. Like when you have the barrel cracked open, and before you cock it.
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You're probably trying to put the barrel straight in. Can't do that. It has to go in at an angle to the compression tube. Like when you have the barrel cracked open, and before you cock it.
The only problem with this position is that the cocking-arm can not be inserted into the cocking-slot unless the angle of the barrel to the compression tube is perfectly parallel. That's one mod I've meant to do, so that you can insert the cocking-arm, and then angle the barrel into the forks at an offset and insert the pivot-bolt. It would only take a little bit grinding from what I can see.
The way I got around it is honestly probably more dangerous than what should be recommended without a heavy disclaimer: YOU SHOULD NOT DO IT LIKE I DID IT. Instead of relying on the pivot bolt, I placed an allen wrench in through the barrel pivot and both forks, and used that to cock the rifle. Then once the spring tension was taken up by the sear, I raised the barrel up, and quickly replaced the allen wrench with the pivot-bolt. That creates a very precarious position for the rifle to be in if the sear let go and there was no pivot bolt. I just made sure I had ahold of both ends of the rifle (my hand on the muzzle, the butt wedged between MY butt and the couch I was on ) and was quick to replace the wrench with the bolt.
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Yes you can. The cocking link pivots at the breach. Put the link at a 90 degree angle to the breach, and insert it in the cocking slot. Then, rotate the breach into position, while holding the cocking linkage tight to the comp tube with the off hand. There isn't a break barrel gun, that l know of, that can't be disassembled, or reassembled in this fashion.
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Yes you can. The cocking link pivots at the breach. Put the link at a 90 degree angle to the breach, and insert it in the cocking slot. Then, rotate the breach into position, while holding the cocking linkage tight to the comp tube with the off hand. There isn't a break barrel gun, that l know of, that can't be disassembled, or reassembled in this fashion.
I'm having a hard time visualizing this, would you mind posting some pictures? Just to be clear, are you doing this while the piston and spring are both inserted, and the piston is fully in its forward position?
I remember trying to do something like this, but the piston being kept forward by the spring meant the pivot would never line up with the holes in the forks until it was in a totally closed position. Otherwise the spring would prevent the cocking arm from moving the piston around freely, not allowing the pivot and holes in the forks to be kept aligned through the rotation.
I don't have a jig to remove the spring while the barrel is on, so I have to remove the barrel, and then put the compression tube in a bar clamp. It's only ever been an issue with this rifle because it doesn't have a second pivot in the cocking-link like my Crosman Vantage does.
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So Glad I subscribed to this thread.
You guys are awesome in your knowledge.
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I'm having a hard time visualizing this, would you mind posting some pictures? Just to be clear, are you doing this while the piston and spring are both inserted, and the piston is fully in its forward position?
I remember trying to do something like this, but the piston being kept forward by the spring meant the pivot would never line up with the holes in the forks until it was in a totally closed position. Otherwise the spring would prevent the cocking arm from moving the piston around freely, not allowing the pivot and holes in the forks to be kept aligned through the rotation.
Sorry I don't have any pictures handy, at the moment. And, yes, the piston and spring are in the gun.
Question for you. When you look at the cocking shoe in relation to the piston's cocking slot, ( with the gun assembled, and the barrel closed completely ), do you see a small gap between the end of the cocking shoe, and the end of the slot in the piston??
If so, then you are able to disassemble / reassemble the gun, as I described. If NOT, and the cocking shoe is touching the end of the of the slot in the piston, you need to shorten the cocking shoe by about a 1/32". If you don't, it is possible that the piston isn't coming fully to rest against the front of the compression chamber, and that will eventually cause excessive wear to the cocking shoe, or, possibly break that part of the lever, completely.
There should be no pressure from the piston spring on the barrel / cocking link assembly between the point where the barrel is fully latched in battery, and again just free of the barrel detent.
In other words, you should be able to crack the barrel open, without cocking it, and have an unobstructed view of the back of the bore, just above the compression tube, without the piston spring trying to force the barrel closed.
Make sense??
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I'm having a hard time visualizing this, would you mind posting some pictures? Just to be clear, are you doing this while the piston and spring are both inserted, and the piston is fully in its forward position?
I remember trying to do something like this, but the piston being kept forward by the spring meant the pivot would never line up with the holes in the forks until it was in a totally closed position. Otherwise the spring would prevent the cocking arm from moving the piston around freely, not allowing the pivot and holes in the forks to be kept aligned through the rotation.
Sorry I don't have any pictures handy, at the moment. And, yes, the piston and spring are in the gun.
Question for you. When you look at the cocking shoe in relation to the piston's cocking slot, ( with the gun assembled, and the barrel closed completely ), do you see a small gap between the end of the cocking shoe, and the end of the slot in the piston??
If so, then you are able to disassemble / reassemble the gun, as I described. If NOT, and the cocking shoe is touching the end of the of the slot in the piston, you need to shorten the cocking shoe by about a 1/32". If you don't, it is possible that the piston isn't coming fully to rest against the front of the compression chamber, and that will eventually cause excessive wear to the cocking shoe, or, possibly break that part of the lever, completely.
There should be no pressure from the piston spring on the barrel / cocking link assembly between the point where the barrel is fully latched in battery, and again just free of the barrel detent.
In other words, you should be able to crack the barrel open, without cocking it, and have an unobstructed view of the back of the bore, just above the compression tube, without the piston spring trying to force the barrel closed.
Make sense??
Yeah I think I know what you're getting at! In fact I've always noticed a bit of damage to the piston where the cocking-arm is seated into it as if the piston is slamming onto the end of the cocking-shoe.
I don't have my rifle here with my, I left it at my buddy's house since that's where I go shoot it at anyway. I'll have to remember to bring it home to check all this out with. Thanks!
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Well, late summer got a bit too hot for shooting and then the fall/winter so I finally got to shooting this rifle a little more recently, and I definitely did a butcher job on this tune-up :/
Big problem is I didn't really document everything I did quite well. At some point I ended up swapping back and forth between seals, and I think both of them were a little undersized. One was undersized because I made it that way ( the stock, blue seal ) and then there was another one that's in there now that's (after-market, clear seal) that's made of nylon and I got from Jeff. After my last post about not getting the numbers I expected, I did a little more testing with a chronograph.
https://www.gatewaytoairguns.org/GTA/index.php?topic=131423.0 (https://www.gatewaytoairguns.org/GTA/index.php?topic=131423.0)
According to that post, I say...
"I can only find one place to get a seal that looks like the factory one that was a little "snug", to try to size the seal. I tried with the factory one, but over-did it. This after-market nylon one is clear and is the one that's a little loose, and also the one you can buy at most outlets. The blue/green Norrica one is the one they're using from factory but I can only find it from one outlet."
Was really wondering what could be going on, even thinking the temperature/humidity differences could be causing it since I was getting consistent numbers, just lower. Finally had my "eureka" moment asking about seal resistance just recently...
https://www.gatewaytoairguns.org/GTA/index.php?topic=142332.msg1441511#msg1441511 (https://www.gatewaytoairguns.org/GTA/index.php?topic=142332.msg1441511#msg1441511)
Basically I realized what was going on was the seal being slightly undersized, but being of the parachute design, was traveling a certain amount down the tube losing compressing until the drag caused it to parachute and it sealed. That's why I was getting the lower, yet still consistent numbers. I posted these figures at the start of the "Still shy a few ft/lbs" thread...
888
820
871
867
861
859
846
21.38089935 sd
858.8571429 avg
68 es
858 fps with a 7.4 gn pellet is 12.1 ft/lbs according to ChairGun
Well I was cautioned against using the lighter 7.4 grain pellets so I went and got some 10.5 grain ones, but they weren't really giving me the accuracy I wanted, and they weren't "sealing up" the barrel or adding any extra cushion against the piston seal like I wanted so I didn't see much of an energy increase with them.
I chronied a 22 shot string with them a couple weeks ago which didn't seem bad, not sure why I couldn't hit &^^& with these, but still showing the lack of power...
716
734
726
723
725
731
739
731
733
725
732
731
734
732
720
736
733
728
728
721
725
High: 739
Low: 713
Average: 728
Spread: 26
Sd: 6
739 fps with 10.5 grain = 12.7 ft/lbs
So not being satisfied with the 10.5 grain performance, and having shot thousand upon thousands of 7.4 grain pellets with this gun PRIOR to the lube-tune, I decided to get a tin of those and chronograph them... And welp, that's when I broke the gun.
I did a 30 shot string with my Vantage NP, so I decided to do 30 shots with the Kodiak X2, and as you can see things went quite bad ( from last to first shot )
691
71
711
712
737
739
730
727
735
731
149
766
754
780
768
781
803
810
796
769
811
791
241
812
825
800
807
838
826
829
840
So not much point in getting the statistical data, but as you can see the MV pretty much gradually trended down and by the time it was at that point, I could smell the barrel dieseling. I gave it a few minutes to cool down and tried again, but it was still only in the high 600s and I decided not to shoot it much more to avoid damaging it further.
The fact this gun can't digest the 7.4 grain ammo it always did with the factory ( tighter) seal as it did with the newer ( looser ) seal corroborates the whole, "I've been shooting with too loose a seal" idea, and it seems like something finally gave. Hoping the seal finally just gave and I will just need to replace it rather than something more significant in the rifle being broken.
I'll have to tear it down and get pics tomorrow when I have light for better pictures ( no flash on my camera ).
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Okay, got the gun apart, and got pictures of the seal. There's no question it was too loose, I can turn the compression tube over to one angle or the other and get the piston to slide back and forth. It seems like it was shedding chunks off of it.
What worries me is that I think this was a fresh seal so it shouldn't have been that loose to begin with. I'm hoping that I didn't over-do it when I tried to polish the compression tube with sandpaper.
(https://i.imgur.com/B9UuJfn.jpg)
(https://i.imgur.com/esJf22E.jpg)
(https://i.imgur.com/K7KDt7W.jpg)
(https://i.imgur.com/fDXouNf.jpg)
(https://i.imgur.com/kKv06Xm.jpg)
Not quite sure what I will do if I ended up enlarging the compression tube too much, but I will need to get another seal just to test. For now the gun exists as a bag of parts :/
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Where did all that stuff on the front of the seal come from?
:o
When doing the compression tube you only want to scuff it not bore it out.
I only do 4 or 5 real quick up and down strokes with 400 grit wet/dry in a bucket of water with a few drops of dish soap.
You want another compression tube (already scuffed and deburred) with the piston and a new seal?
I'll even throw in a bit of the Krytox lube I have on hand.
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Where did all that stuff on the front of the seal come from?
:o
When doing the compression tube you only want to scuff it not bore it out.
I only do 4 or 5 real quick up and down strokes with 400 grit wet/dry in a bucket of water with a few drops of dish soap.
You want another compression tube (already scuffed and deburred) with the piston and a new seal?
Oh man that would be great! Please save me from myself! haha
Yeah by the sounds of it I definitely over-did it then. I wrapped the sandpaper against the dowel so that only a flap was making contact with the tube and it wasn't firm, but I guess with all that RPM and extra time spent, it must have removed enough thousanths of an inch.
As for all that debris, that's exactly what I was wondering. I think those are little bits of plastic from the seal itself, because the middle of it is kind of chewed out a little bit, almost like the screw was shearing off bits of it as it smashed into the tube.
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That stuff looks like burned off Moly lube to me.
If you use the krytox? Don't over do it! A little goes a LONG WAY! (same with moly)
You really only want enuff to assist the piston going in. Nothing more.
I'll double check the compression tube I have here before I ship it all.
IF you let sand paper loose like that? You'll not get a round sand effect.
The paper will jump and slap and you get a tube that has high and low spots.
I use some of the insulation you put on water pipes to get a kind of snug fit then wrap the paper around that.
Just a few real quick passes up and down and stop! Your only breaking the glaze to hold any lubes and/or remove
old burnished in garbage.
I'd say one could do a quick pass or 2 with 400 grit then do another couple with 600 and call it a day.
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This post got me thinking about my old Beeman dual cal. It has had all kinds of ammo sent down both barrels for over 6 years , and got extra wear and tear being my only air rifle for over 2 years. Still shoots accurate as heck but I am sure it is on its last legs.
So it is sitting on my work bench awaiting a tear down and inspection.
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I still have several versions of this Beeman gun in the parts trunk.
If you need a part let me know. I might have it.
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That stuff looks like burned off Moly lube to me.
If you use the krytox? Don't over do it! A little goes a LONG WAY! (same with moly)
You really only want enuff to assist the piston going in. Nothing more.
I'll double check the compression tube I have here before I ship it all.
Oh okay, I did use molly. Though I thought I used it sparingly enough this time because I didn't have any dieseling problems on the first few shots when it all went back together. I wonder if maybe the bit I put on the following-section of the piston somehow traveled into the compression tube in front of the seal? I might really not have a good idea of how sparingly it needs to go on. I used a tiny dab about 1-2 mm in diameter and paper thin on the seal, but a pretty good helping on the follower and in the cocking-slot area.
I've been thinking about trying Krytox instead, but I still have a heaping jar of JM molly paste. But the whole not-dieseling factor is a pretty appealing reason to switch and just use the molly on other areas.
This post got me thinking about my old Beeman dual cal. It has had all kinds of ammo sent down both barrels for over 6 years , and got extra wear and tear being my only air rifle for over 2 years. Still shoots accurate as heck but I am sure it is on its last legs.
So it is sitting on my work bench awaiting a tear down and inspection.
I think I probably could have waited a while longer before opening mine up just going by the looks of it, but what was really causing my roughness in the shot cycle was the cocking-foot grinding against the bottom of the piston. Still need to go over longhunter's post to be sure of it, but I think I rammed the piston into the cocking-linkage a little too hard a time or two by accidentally dry-firing. Otherwise it held up pretty well over 3 years of being my only rifle, and I don't know how many thousands of pellets.
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Any lube you use? You don't want much!
That piston is slamming forwards and any build up will follow the laws of momentum.
Just like a person in a car with no seat belt and the car hits a tree!
Your getting bits and pieces of both off of something it shouldn't be on!
Given you used a slap sander in your tube? Yep. I can see excess moly passing the round seal in a not round tube.
;D
Moly doesn't diesel much so it don't surprise me you may have missed it.
It's more a smell thing with that stuff.
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And going back looking at your seal pictures real close?
I can see the chamber is out of round.
Look at the color differences near the seal lip.
See how some spots are dark and others are almost clean? That is wrong!
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OK. Dug the compression chamber and stuff out.
This has a brand new seal and spring. I don't like the fit of the rear spring guide so I'm going down and turning a new delrin guide for it. It will fit tighter and help reduce spring twang.
I'll send both with the package.
This piston is not buttoned but I'll include old school buttons you can glue on if you want.
You'll need to clean the piston REAL good and use NEW super Glue then sand to fit.
You will NOT need to lube this assembley! It's all been done.
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And going back looking at your seal pictures real close?
I can see the chamber is out of round.
Look at the color differences near the seal lip.
See how some spots are dark and others are almost clean? That is wrong!
OK. Dug the compression chamber and stuff out.
This has a brand new seal and spring. I don't like the fit of the rear spring guide so I'm going down and turning a new delrin guide for it. It will fit tighter and help reduce spring twang.
I'll send both with the package.
This piston is not buttoned but I'll include old school buttons you can glue on if you want.
You'll need to clean the piston REAL good and use NEW super Glue then sand to fit.
You will NOT need to lube this assembley! It's all been done.
Any lube you use? You don't want much!
That piston is slamming forwards and any build up will follow the laws of momentum.
Just like a person in a car with no seat belt and the car hits a tree!
Your getting bits and pieces of both off of something it shouldn't be on!
Given you used a slap sander in your tube? Yep. I can see excess moly passing the round seal in a not round tube.
;D
Moly doesn't diesel much so it don't surprise me you may have missed it.
It's more a smell thing with that stuff.
Well glad I got those pictures so crisp to figure out how I screwed it up. Guess that sandpaper on a dowel idea wasn't such a bright one. D'oh!
I'll be sure to remember not to add any extra lube this time. Excited to get it back to shooting good again! You're awesome, Jeff.
Yeah those delrin buttons sound like they'll be a lot better than my JB welded ones too haha
I'm thinking about investing in some Krytox for future endeavors. Like you were saying, I think the molly has been dieseling and I just don't notice it. Probably need to tear down and re-lube my Vantage as well.
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OK. Dug the compression chamber and stuff out.
This has a brand new seal and spring. I don't like the fit of the rear spring guide so I'm going down and turning a new delrin guide for it. It will fit tighter and help reduce spring twang.
I'll send both with the package.
This piston is not buttoned but I'll include old school buttons you can glue on if you want.
You'll need to clean the piston REAL good and use NEW super Glue then sand to fit.
You will NOT need to lube this assembley! It's all been done.
Hey Jeff, finally got it all put together and broken in. Thanks buddy!
It dieseled for a little bit, but wasn't so terrible, and I still have a good bit of the 500 ct tin of 14.3 gn Crosman pellets I got for it. All I have for it scope wise right now is the 4x32 scope it came with, and my eye-sight is terrible, so I haven't been able to really shoot very many awe inspiring groups, but I was pretty proud of getting it into 1" CTC at 24 yards with that low magnification.
Now it truly is a whole new beast... Completely different tube! Haha
So far the chronograph figures with CPHP 14.3 grain
Muzzle Velocity
Min: 672 FPS
Max: 701 FPS
Avg: 682 FPS
SD: 8.43
Spread: 10
Muzzle Energy
Min: 14.43 ft/lbs
Max: 15.61 ft/lbs
Avg: 14.77 ft/lbs
Velocity @ 24yds
Min: 584
Max: 612
Avg: 601
SD: 10.87
Spread:28
BC: .0213
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So everything is working better then?
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I don't care what Rocker says about you, Jeff. You're alright. :D :D
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AMAZING!!!
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I don't care what Rocker says about you, Jeff. You're alright. :D :D
Don't be spreading that rumor around about me being alright!
I have a reputation to maintain!
:D
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"
Butt Stock Licker".
There, you're welcome.
;D
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I have a friend who has one of these airguns and he has wanted to try a tune on it.
This thread will sure help him alot.
Thanks
Ray
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So everything is working better then?
Doing great! I still need to find some heaver .177 pellets, or some .22 pellets that it likes to test accuracy. I think the gun is more capable than I am, but so far I can get 1" at 25 yards if I try real hard, and at 15 yards without really trying. So that's pretty good to me, and it isn't ringing my ears every time I shoot it now either. I think I'm going to avoid using any light pellets in it from now on.
Thanks again man!
ray1377, glad I can help, be sure to check out Jeff's original rebuild thread that I learned from.
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Sure is fun seeing you keeping on with this tuning path!
Wish I could get your freehand groupings!
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Sure is fun seeing you keeping on with this tuning path!
Wish I could get your freehand groupings!
I wish I could get consistent groups! One day it's under 1 inch @ 24 yds, the next it's closer to 1.5 inches @ 15.
Meanwhile, I've had some pretty good strings, and then I'll get a flyer, so I've been trying to run long groups. Over 5, between 10. I believe the ammunition being inconsistent is probably the biggest culprit, from my ammo tests in the past, so I think the few groups that have stacked up are promising.
I also decided to tar my spring a little more and I'm glad I did. There was just TOO much noise without the spring heavily tarred, and it really kind of hurt my ear to shoot. Now it's a much quieter "thwok" sound that sounds like a gun shooting, where before it sounded more like a duck trying to hack up a lung.
Anyway, aside from the lack of being able to get good groups, I will get some pretty good 1st try shots. I decided to zero at 15 yards since I'm using the limited 4x scope, until I can get a Hammer's 3-9.
I did some more chronograph testing, and I really believe that the ammunition has to be the cluprit given the widely varying velocities, yet the patterns of some being close together. That also shows up in my groupings, where 2-3 shots will stack on top of each other, but then land 1/4" - 1/2" or more away from each other on paper, along with the random flyers. I know it likes JSB and AA stuff more, so I'm going to wait until I get some of those to get the Hammer's scope and do more extensive accuracy testing.
This pic shows what I mean pretty well... I got it zero'd in, but notice how I get two pretty distinct groups where they're stacking, and then fliers all over.
(http://i.imgur.com/ffI0bCS.png)
This one was going good for a while too and then the fliers made their appearance, but that first ragged hole group was a 3-shot string, so I think the rifle has the potential.
(http://i.imgur.com/oSuNm0M.png)
Recent chrony figures after the spring tar...
(Last to first)
688
690
685
660
684
686
661
672
683
678
683
688
674
661
669
Hi: 690
Low: 660
Avg: 677
ES: 30
SD: 10
It kind of seems like there's a few repeating figures. It seems to end up ~660, ~670 and ~685 a lot.
I took some shots at 15 yds to test the BC again and got a little closer to .019
I found some of the old pointed pellets the other day so I might try some of those too, but I doubt I'll see much improvement given my previous tests with the Crosman offerings.
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My Sportsman is VERY hold sensitive. Even shooting from a bench, I have to place rests and sliding surfaces PRECISELY, and anchor the cheek in the same exact position, and hold the stock with exactly the same pressure, to get any kind of grouping.
Others have FAR more shooting experience than I do, but it looks to me like you have the gun itself nicely dialed in... the rest is the hold.
I'd have asked if you checked your screws, but that first picture shows two pretty close groupings. Can't imagine you'd get those with loose screws!
One thing about cheek weld... I found that scope to be extremely sensitive to that! I put a piece of tape on the stock, so I could repeat consistently. I think it has something to do with exactly where the reticle is in the optical chain.
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My Sportsman is VERY hold sensitive. Even shooting from a bench, I have to place rests and sliding surfaces PRECISELY, and anchor the cheek in the same exact position, and hold the stock with exactly the same pressure, to get any kind of grouping.
Others have FAR more shooting experience than I do, but it looks to me like you have the gun itself nicely dialed in... the rest is the hold.
I'd have asked if you checked your screws, but that first picture shows two pretty close groupings. Can't imagine you'd get those with loose screws!
One thing about cheek weld... I found that scope to be extremely sensitive to that! I put a piece of tape on the stock, so I could repeat consistently. I think it has something to do with exactly where the reticle is in the optical chain.
Ohh yeah I forgot I was experimenting with hold positions too, but I don't remember which group was with what hold. I either rest my palm about an inch forward of the trigger guard, or a little further up where there is that division between the checkering on the stock. It seems like the position behind the trigger guard is best, but it also seems to vary depending on the angle of the shot if it's inclined versus declined. In other words, the best spot seems to move forward on the stock the more the shot angle declines, but I can't get a sense of exactly where.
I was playing with declination as well. It deviates a lot with even a minute angle change, and closer ranges seem to be more problematic sense it exaggerates the difference in declination when aiming for the top or bottom of a target at 15 yards vs 25 yards. In other words, to aim at a target 12" below the previous one would mean a 5 degree declination at 25 yards, but almost 10 degrees at 15. So while one hold works well at that yard range for one group, when I aim lower, the hold is no longer optimal because the gun is then at such an exaggerated from the previous group. It's not as noticed shooting at 25 yards or more, but thanks to the exaggerated changes at 15 yards, I finally realized it was a factor.
Anyway rambling...
One weird thing about the stock screws I noticed is this stock didn't fit the tube Jeff sent. The forearm screw-hole on the right side of the stock wasn't flush with the hole in the tube, though the rear stock screw and the left forearm screw hole both were. Not sure what could account for that (probably just the stock warping over time?), but since the other two holes were flush, I just reamed out the other hole a little oblong so the bolt would fit. It only took a few millimeters, but I reckon that could account for assymetry in the vibrations and reverberations. I couldn't begin to guess by how much, or how that would affect hold sensitivity. They're snug at least.
Sometime down the line I want to get a wood rs2 stock for this, because I really don't like the wrist on this stock. Feels like I'm trying to hold a 2x2 it's so square. I wonder if having a heavier stock would dampen out the vibrations and make it less hold sensitive as well.
I have noticed the same with the cheek weld! I think an AO helps a lot with that too, or at least i have noticed the supplied 4x32 is pretty bad about it.
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Ones hold needed for best accuracy in a piston gun can vary with the pellet also, heavier pellets take a little longer to leave the barrel thus a different hold than a pellet weighing a couple grains lighter.
and no matter what you are shooting , always follow through and watch the impact ;)
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Well, it's been quite a while since I went shooting. Lost my spots to go shoot, life stuff happened, etc. Just now getting back to this rifle and trying to make it work better.
I had shot a few hundred pellets out of it more or less since the last time I posted, and was still getting some dieseling, and was still way under the energy levels it should be producing. It was only averaging about 652 fps with 14.3 grain CPHP and from all other figures I've seen, it should be averaging around 730-740 for those pellets. I tried with some Ruger Superpoints too that were 17 grain, and was only getting a 599 fps average, so it wasn't just that my barrel didn't like the CPHP, I was just quite a few foot pounds shy of the energy this rifle should produce.
I decided that since it was still dieseling after all this time that I must have just put too much lube in it, or maybe too much tar on the spring, so I took it apart and cleaned it out pretty well and cleaned the spring off too. After that, I was getting a 694 fps average with the 14.3 grain CPHP and 645 with the 17 grain Ruger Superpoint, so it seems that either the lube or the heavy tar on the spring was slowing it down quite significantly.
I realized that I messed up by lubing the following end of the piston quite liberally with molly paste. I didn't put very much on the seal, but what happened was that the seal was basically mopping up the molly that was being smeared onto the tube by the following end of the piston, and pushing it into the front of the chamber. There was quite a lot of blackened soot up there from it dieseling, but thankfully the seal was still in good shape.
It's still dieseling unfortunately, so I must need to clean out all the gunk that's still inside of the piston where the top hat is seated on the spring too. I didn't think that area would cause dieseling, but it's the only area with combustible material left in the chamber, so it's got to be the culprit. Might just be because of how much is in there... There's so much molly paste and heavy tar inside of it, the top-hat just sits up there without falling out.
I'm considering filing off the JB Weld buttons I put on the back of the piston too. I don't know that they're doing any good, and from what I can see they're steadily wearing away, and probably won't last a few thousand more shots anyway. I can't imagine that they produce less friction than steel-on-steel anyway.
But so far I'm pretty pleased with the numbers I got today after cleaning up the mess...
CPHP 14.3 Grain...
5 shots...
High: 704 fps
Low: 688 fps
Avg: 694
Sd: 5
Ruger Superpoint 17 Grain
10 shots...
High: 651
Low: 630
Avg: 645
Sd: 6
Numbers are pretty consistent shot-to-shot despite the continued dieseling, and those SDs are nice and low. Usually I like to test over 30 shots, but I was testing inside today and don't have a good pellet trap so I'll have to wait until I can take it out somewhere to test some longer strings. Plus i figure not much point in wasting too many pellets to since I'm assuming the gun will have to settle back out again.
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It is easy to over do the lubricants. Now that it is cleaned up maybe just shoot it more, shooting seems to be part of the breaking in process.
Good work,
Pat
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It is easy to over do the lubricants. Now that it is cleaned up maybe just shoot it more, shooting seems to be part of the breaking in process.
Good work,
Pat
Yeah this gun seems like it has a real Goldillocks syndrome when it comes to how much lube to use. I swear my B19 was nowhere near this finnicky; that was a one-and-done job.
After taking all of the lube out and running it dry, I eliminated the dieseling, but it dropped back down to 650 fps with the 14.3 grain.
H: 663
L: 646
AVG: 653
SD: 5
An SD of 5 is pretty good and the numbers were quite consistent, so I didn't see much reason to believe it would "settle" into better figures. Added a little bit of lube, first shot was back up to 699 with the 14.3 grain.
H: 699
L: 670
AVG: 684
SD: 10
It seems to have settled out a bit more the more I shot over the chrony as I tested the 17 grain Ruger Super Points...
H: 650
L: 627
AVG: 636
SD: 7
So I think NOW I should actually wait for things to settle and get more consistent numbers. Hopefully it settles back into the higher ranges produced as the lube is distributed, seal sets, etc. Though I have a feeling as the excess lube burns off, some of the energy will subside.
It's getting kind of frustrating. This gun produces 15-17 ft/lbs stock, so I'm really not satisfied with it running at 13-15 ft/lbs with a "tune". I saw a video of a guy with a RS2 that he said had over 5000 shots through it, using the same 14.3 grain CPHP that I'm testing with, averaging 735 fps, and with great consistency. I could live with 50 fps shy, but if I am near 100 fps shy of that then I must be doing something wrong.
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What elevation do you live at? The higher you live the less velocity you'll get. Find out what elevation others are getting their vel numbers at so you can compare apples to apples.
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Great point Robert.
SagaciousKJB: I have a Silver Kodiak RX2 that is unmodified inside. I should be able to get you chrono numbers with CPHP this weekend if not before if you would like them.
To Robert's point, I am at 1000' above sea level
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Great point Robert.
SagaciousKJB: I have a Silver Kodiak RX2 that is unmodified inside. I should be able to get you chrono numbers with CPHP this weekend if not before if you would like them.
To Robert's point, I am at 1000' above sea level
I'm somewhere around 1100-1200 feet so I think that would probably be pretty close yeah?
How much does air temperature play into it too?
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How much does air temperature play into it too?
Minute for a springer compared to Co2... I am ~68 degrees indoors.
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That's what I figured. I did some.chrony testing outside the other day when it was somewhere between 30-40 F but just remembered I posted numbers I got during summer weather, and they seem pretty close.
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Well, I have really been chasing my tail with this. I've had to have taken it down and put it all together again close to a dozen times or more over the last few days, trying different things...
Slight lubrication on the piston end (wipe on molly paste, wipe it back off), with a thin ring on the back end of the piston seal
No lubrication on the piston end, but a thin ring on the back of the piston seal
No lubrication at all
Slight lubrication on the back of the piston seal, slight lubrication on the piston end, and some clear-tar on the spring-guide only
And many combinations in between.
After reading back through my last few posts I realized that the only variable that I hadn't "put back the same way" when I reached 15 ft/lbs was the JB Weld buttons, so I put those back on and lubed it like I did when I reached that energy level (very thin layer of molly paste on the back end of the seal, slight molly paste on the piston end, no tar on the spring), and there we go, back up to 15-15.5 ft/lbs. So apparently the JB Weld buttons did in fact do something after all?
Now another problem... With the JB Weld buttons on the piston end, and no molly paste, I'm getting some grinding on the cocking cycle. That was surprising since I figured the button should have prevented metal-metal contact, but I think since they are so thin (literally only a few thousandths of an inch) the buttons must compress a little and allow some metal-metal contact on the back of the piston during cocking, because of the way the cocking-shoe presses the piston up against the tube. So I put a little molly paste on the JB Weld buttons. That seemed to help a little, but then the grinding came back after about a ten shots. Not only that, but because the seal is dragged ALL the way back to just shy of the cocking-shoe insert, the front of the seal picks up the molly-paste that was left on the back of the piston-end, and kind of scoops it into the front of the compression chamber--so now it's dieseling again. So unless I use a very little amount of molly paste on the piston's following end, it's going to gall and grind; but if I use enough to mitigate that, it's going to be picked up in the front of the chamber and cause dieseling. It's not dieseling enough to cause detonation, but I'd still prefer not to have a smoky barrel and the smell of burnt molly paste.
It makes me really curious how others with this rifle lube up the piston-end enough to avoid this galling problem, but also avoid the seal picking it up and pushing it into the front of the compression tube. I kind of wonder if maybe people don't consider it "diseling" unless it actually detonates versus just smoking up the barrel. I could see people concluding that theirs is not dieseling under those conditions when it is in fact combusting the lubricant. If that were the case, it would also make me question how much of the higher energy levels of 16-17 ft/lbs I've seen are really attributable to combustion more than air pressure alone.
I also wonder why the energy level was so affected by the JB Weld buttons on the end of the piston. I was just trying to replicate the conditions in which I achieved the 15 ft/lbs of energy, so added them back, not actually expecting them to make much difference. Like I said, I had tried dozens of different combinations without them, but as soon as I added them back, I got back up to that level again. The only theory I could propose about this is that without the buttons, the piston and tube are somehow coming into a greater level of contact during the firing cycle, just by merit of the tube not staying completely aligned, causing one side of the piston to make contact with the tube with a greater surface-area. By adding the buttons, it keeps it "straighter" and reduces the contact surface-area during the firing cycle, and so reduces the friction. However, as feasible as that theory may sound in my head, it doesn't really seem like the amount of friction that could be reduced is really that high, but on the other hand it seems like it can't just be a coincidence that after all the trials I've done, that I immediately get back to the 15 ft/lbs once I add the buttons back.
That goes back to the, "But what if it was just because it was dieseling," idea, because I do clearly remember it was dieseling during that prior trial where the buttons were present on the piston and I reached 15 ft/lbs, but also dieseling when they weren't present and falling shy of the 15 ft/lbs. So I do believe the buttons somehow help, but it made me look back at the numbers I've logged, and realize that during trials where I had reduced the dieseling substantially, it also had substantially lower energy numbers.
But it makes me wonder: Are the higher energy levels the result of the combustion, or is the combustion just an unfortunate side-effect of their being adequate lubrication that reduces the friction enough to reach higher energy levels.
I also have to wonder why even the most minute amount of molly paste on the piston end is being picked up by the seal and pushed into the front of the compression tube. I don't have this problem on my B19, but I have an over-sized seal on that. I think maybe the over-sized seal pulls all the molly-paste back on its cocking cycle, not allowing any of it to linger in front of the seal and end up pushed into the front of the chamber. But there's really not as many seal options available for this as there is for the B19, so I doubt finding an oversized seal for it is going to be an option.
Anyway, I'm rambling, but yeah I've really been chasing the dragon on this one trying to get those higher energy levels. I think I'm going to have to give up on trying to get it properly lubricated with molly paste and opt for some Krytox instead. That should show if the higher energy levels are really down to combustion or lubrication.