GTA
Airguns by Make and Model => Beeman Airguns => Topic started by: WyoMan on December 19, 2019, 11:21:59 PM
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Mods:
1. Auto Safety to Manual
2. Weight / Balance
3. Trigger and components
4. Barrel
5. Piston
First thing I do is strip it to the bone. It’s easier that way:
(https://i.imgur.com/pkHAkOV.jpg)
Auto Safety to Manual
This shows the spring-loaded lever that pushes the safety back when the overlever is closed:
(https://i.imgur.com/cJ5X9tj.jpg)
To remove, drive out the pin shown below:
(https://i.imgur.com/Qp9QvQE.jpg)
(https://i.imgur.com/oxmdLFj.jpg)
The Safety still works but will now be manual…
Fire:
(https://i.imgur.com/vGFELYQ.jpg)
Safe:
(https://i.imgur.com/mxEkdWf.jpg)
Adding Weight and Balance
This is a matter of preference, but I think that adding weight to the bottom grip panels improves the balance and feel…
(https://i.imgur.com/kWEgRYT.jpg)
Lead Shot:
(https://i.imgur.com/0LNLfxk.jpg)
Filled with Epoxy:
(https://i.imgur.com/P3Tz6KQ.jpg)
Up next is trigger mods
Wyo
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Gary, you rock!
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Go ahead and make this a sticky..... ;)(Glad I got more than one. After the first one, the rest should go faster... ::))
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Thanks guys.
Terry, I've hacked up three of them and a HW40 :o I've got a new barrel design, my third and I think it will be the best...
Wyo
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subscribed
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Great, keep going..
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Love it, Gary.
One thing I do feel compelled to warn..
Many of us, at least I, lay the pistol on our thigh to close the receiver after loading. With the auto safety removed, please be sure to keep your finger away from the trigger or you run the risk of the gun firing.
Those of us who opt to lighten the trigger run an added risk of premature firing.
I have removed the safety on my personal gun but left it functional on Betty Lou's and any gun I let others use.
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Wow, Garry you're them bomb. Keep it going. Follow with much interest. And yes a +1 for the Stickie.
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Great idea for a sticky with all the bargain gate P17s that were purchased.
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Thanks, guys.
Bill, we sometimes forget to mention caution when showing the modifications… thanks for that.
Trigger and Components
The latch / unlatch (break) occurs between the sear and the intermediate lever.
Those surfaces (circled below) slide against each other and may benefit from some light smoothing:
(https://i.imgur.com/ahIcTSI.jpg)
The intermediate lever also moves between the wire guides that are inside of the hammer. This is another potential area to smooth.
Shown below with some 600 grit rolled up that I will work up and down (just one way to do it):
(https://i.imgur.com/BXqtEcx.jpg)
You can replace the fixed first-stage with an adjustable first-stage. The P17 trigger is pretty good right out of the box. This mod just adds some more adjustability.
Remove the hardened steel pin:
(https://i.imgur.com/3Uxp4BQ.jpg)
I drilled thru the trigger with a 3/32” drill and tapped 4-48:
(https://i.imgur.com/xOlR5eE.jpg)
(https://i.imgur.com/ol7vsf8.jpg)
Using an alloy steel 4-48 setscrew for the first-stage contact:
(https://i.imgur.com/Iwfv6hW.jpg)
As Bill mentioned above, modifying the trigger can make it unsafe. These pistols are prone to getting a jolt when the over-lever is closed.
And when that occurs, the pistol is probably loaded, cocked and charged. To keep it safe, you need adequate trigger spring tension and the subsequent engagement between the intermediate lever and the sear.
As far as I know, the only way to have it both crisp and safe is to have both stages engaged with the break occurring on the second-stage.
Putting the trigger components back together and making adjustments…
(https://i.imgur.com/1DKz1Ig.jpg)
(https://i.imgur.com/EZ4M4um.jpg)
The above shows the hammer in the cocked position. The circles show the sear locking the hammer and the intermediate lever locking the sear.
I like to test the first-stage to see if the trigger spring will reset everything when you let off… if it doesn’t, there’s probably something wrong.
Up next is a longer barrel (Lothar Walther)
Wyo
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Gary,
Great stuff, superb pictures! I have followed your work here and on CAPOF for a few years. None better!
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Thanks, Craig… been awhile since I checked-in over there but had lots of good times.
Longer Barrel
There’s more than one way to do this. I’ve done it three different ways but this has been the easiest so far.
The barrel is a Lothar Walther for a Crosman 2300S. It’s about the right length and diameter for what I want to do.
Parted off the transfer port, faced and chamfered the new breech, cut the new leade and plugged it with a pellet:
(https://i.imgur.com/P0VOiBz.jpg)
Turned just the bare minimum here and then cut the corners so it would be easier to slide in and out:
(https://i.imgur.com/hcieO8l.jpg)
The frame will need a couple alterations for the longer barrel.
A clearance cut is necessary on the lower frame (below the pivot) in order to get a full intake stroke:
(https://i.imgur.com/5EFiu1H.jpg)
(https://i.imgur.com/vi7Gkrp.jpg)
Depending on the o.d. of your longer barrel, you’ll have to drill something thru the muzzle. This one was drilled 7/16”:
(https://i.imgur.com/hV33nto.jpg)
I’m also adding a couple setscrews to secure the barrel because the muzzle restraint was drilled out and is gone.
These were drilled 1/8” and tapped 8-32. A second set will be added to lock the lower set.
The barrel was left a couple thou oversize and that turned out pretty well… it’s a nice snug fit:
(https://i.imgur.com/3hUbUlA.jpg)
The new barrel is 9.7” long… 3” longer than the oem barrel. Getting closer here:
(https://i.imgur.com/JZJyKJb.jpg)
(https://i.imgur.com/HhpI2dq.jpg)
It doesn’t shoot yet because it doesn’t have a piston… still working on that…
Wyo
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Last mod – Piston
This shows the original piston (minus cheap oem o-ring):
(https://i.imgur.com/Fntl8rO.jpg)
The mark on the piston is how far it comes out of the cylinder at the end of the intake stroke… that established the location for the back of the oil wick groove.
Groove is cut .120” deep and .250” wide:
(https://i.imgur.com/hcoVaNZ.jpg)
The felt is .125” thick F-3. Cut to 5/16” wide it was a really tight fit in the groove:
(https://i.imgur.com/rwajgMk.jpg)
Last thing is the now famous “diametrically channeled shim”… and a better o-ring (UC70D 116):
(https://i.imgur.com/fx4xYiX.jpg)
(https://i.imgur.com/QGWdsmL.jpg)
The shim is .033” thick JB Weld and coated with cyanoacrylate.
All this for a pistol that cost $7.50…
(https://i.imgur.com/FFKvq3C.jpg)
(https://i.imgur.com/2CI7Jec.jpg)
Wyo
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Very impressive! Got 2 questions though.
1. How did you get the felt washer on without tearing it?
And 2. What oil are you using on the felt? Pellgun or 20wt or silicone?
All "how-tos" should be this well done. You, sir are the pistol master.👍👍
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It is like watching IP Man do his martial arts ;D..
Fun and detailed high resolution photos always make me watch Mr. Gary's posts ;D..
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Great write up. Thanks!
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That piston looks great! I really like the way you did the oil-wiper.
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Great mods! I've been pretty happy with mine stock other than the too looooong second stage of trigger pull. I'm going to have to try out some of your ideas
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It is like watching IP Man do his martial arts ;D..
Haha
True that!
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Very well done.
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Thanks guys.
Terry, the felt wasn’t really a washer per se; it was a strip that was cut to length and width. It was a tight enough fit that the ends will stay tucked in… and of course once it’s in the tube it can’t go anywhere.
I’ve used 30wt ND (pellgun oil) but have had better luck with 20wt ND. The lighter oil seems to work thru the gun better without gumming up in the valve… and any lube you put on the piston will end up in the valve. I’ve never tried silicone oil for this type of application. Thanks again.
Wyo
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Thanks for the clarification. It seems like a mod that should have been factory designed to improve the longevity of these guns. I think Daisy uses felt wipers in their MSPs.
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Been following this... awesome build!
Chrono results ?
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I believe you’re right, Terry. The FAS6004 and the HW75 also have felt oil wicks. I’ve noticed that pistons with oilers have a more consistent lubrication and pump stroke. And you don’t have to be so precise with the frequency and the amount of lube – that’s a big plus for me.
Seems like one more groove with a CNC operation and a nickel’s worth of felt wouldn’t raise the price point much…
Wendell, I did some range time today…
A couple 10-Shot groups from 10m:
(https://i.imgur.com/FN4MeGh.jpg)
Still trying to get used to the laser sight… first time using a laser but I really like it
Chrony:
Before: 365 fps for 2.5 fpe (jsb 8.44 gr)
After: 413 fps for 3.2 fpe with an e.s. of 4
That’s at 7000’ elevation. Folks at lower elevations would probably get a higher fpe. But the pump stroke or closing effort would be more difficult as well.
And regarding the pump / cocking effort… the sight aid is used as a handle to pump (close the lever). That does help and there are lever assist aids as well.
The cocking (opening the lever) can also be improved. If you have cracking, crunching or weird spring noises, then this may help…
Lube the locations that are circled in white:
(https://i.imgur.com/iRfs0dQ.jpg)
Also, the red circle shows the end of the sear spring that was bent outward. The end will now bite into the plastic to keep it from sliding upward and potentially causing misalignment issues. You may not have that problem but if you do, this will fix it.
Hopefully, you only hear and/or feel two noises when you open the lever… the intermediate lever snapping into place (to lock the sear), and the vacuum release at the end of the stroke.
Thanks guys-
Wyo
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Well that kind of threw me. Most of the P17's I've read about started out around 400+-
so I had mistakenly thought you'd be climbing towards the low 5"s lol
And btw Sir, your builds are always outstanding!
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Well that kind of threw me. Most of the P17's I've read about started out around 400+-
so I had mistakenly thought you'd be climbing towards the low 5"s lol
And btw Sir, your builds are always outstanding!
At sea level, he would probably be very close to 500fps.
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Well that kind of threw me. Most of the P17's I've read about started out around 400+-
so I had mistakenly thought you'd be climbing towards the low 5"s lol
And btw Sir, your builds are always outstanding!
At sea level, he would probably be very close to 500fps.
Yep, guess 7000 is really up there!
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Well that kind of threw me. Most of the P17's I've read about started out around 400+-
so I had mistakenly thought you'd be climbing towards the low 5"s lol
And btw Sir, your builds are always outstanding!
At sea level, he would probably be very close to 500fps.
Yep, guess 7000 is really up there!
It's good for PCP and CO2 :D
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Well, guys… I’m still in search of the Holy Grail for SSPs in the thinner air (and springers for that matter). Longer barrels, higher compression, and smaller ports will help but they reach diminishing returns pretty fast.
I did pick up another 5 fps however, lol. Had a minor breech seal leak because the port bulkhead was pretty rough… no before pics, sorry.
The fix was to cut the bulkhead about 20 thou to clean it up. The o-ring has a shallower groove but no problems with that. Repositioned the barrel and all was good… you can still see some remnants of the mess:
(https://i.imgur.com/GU6f9fi.jpg)
Thanks-
Wyo
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I'm so blown away by these mods and envious because I don't have the proper tools nor machining skills to do the stuff like the barrel and piston mods... I love my P17 and everything about it but after seeing this, I'm no longer content. The workmanship is so insanely perfect, *drools*
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Thank you Gary for taking the time to share your wisdom.
Posting for future reference.
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Thanks, guys.
I took it apart today to check the usual suspects for wear and QC issues... all o.k!
Maybe this won't be a disposable throw-away like some in the past.
I still have three in the clamshell and a LW blank in .22 cal... hmmmm ;) ;D
Wyo
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Finally got the laser locked-on, literally.
I use it as a cocking handle and the mounts weren't secure to the rail... they're picatinny (of course) so you have to use an adapter... and the plastic (err.. composite) will cold flow. So it took a few torque sessions over a few days before everything settled down.
10-shot groups from 10m:
(https://i.imgur.com/GRTskC4.jpg)
The P17 in .22 cal is the next project. I'm going to have to go a bit longer with the barrel, nix the choke, and hope that the trajectory will be flatter than a mortar round, lol.
Wyo
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Great accuracy Gary.
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Another awesome P17 thread. You are a master. That is one sweet setup and you are giving me some great ideas.
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I added an arrow to your picture. When I sanded/polished by the arrow the result was a much shorter 2nd stage.
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Last mod – Piston
This shows the original piston (minus cheap oem o-ring):
(https://i.imgur.com/Fntl8rO.jpg)
The mark on the piston is how far it comes out of the cylinder at the end of the intake stroke… that established the location for the back of the oil wick groove.
Groove is cut .120” deep and .250” wide:
(https://i.imgur.com/hcoVaNZ.jpg)
The felt is .125” thick F-3. Cut to 5/16” wide it was a really tight fit in the groove:
(https://i.imgur.com/rwajgMk.jpg)
Last thing is the now famous “diametrically channeled shim”… and a better o-ring (UC70D 116):
(https://i.imgur.com/fx4xYiX.jpg)
(https://i.imgur.com/QGWdsmL.jpg)
The shim is .033” thick JB Weld and coated with cyanoacrylate.
All this for a pistol that cost $7.50…
(https://i.imgur.com/FFKvq3C.jpg)
(https://i.imgur.com/2CI7Jec.jpg)
Wyo
For your JB Weld shim on the piston, what are the benefits of adding the cyanoacrylate and how much thickness do you think it adds?
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Thanks, guys.
Hi Rick, I understand what you did in the drawing with the arrow... you're reducing the amount of engagement between the sliding surfaces.
Other folks have done something similar by increasing the adjustment (outward) of the second stage screw (they defeat the built-in stop by drilling and tapping it thru). You can only go so far with that and keep it safe... you'll still have something less than "crisp" but if it works well for you then that's a bonus!
Have you tried backing out the screw to where it just makes contact before the break? That will give you a crisp second stage without any mods to the oem setup.
Some folks (including me) don't prefer that setting because the trigger is nearly at the rear of the guard when it breaks... which leads them to screw in the second stage and then they have creep... and then they reduce engagement... etc.
The adjustable first stage screw can give you a crisp break on the second stage without the really long first stage - the break occurs with less total trigger travel. And it has a safe amount of engagement because the second stage screw is still in oem configuration.... hope that makes sense.
I use superglue on the JB Weld to seal the surface in case there are minor imperfections. It acts as a mild solvent and as such will soften, seal and congeal.
Don't know if it increases the thickness - never measured before and after. Guessing I'm a bit long-winded here... thanks again-
Wyo
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Gary.... here's a cheap and easy that makes a big difference. Cut a 3" <> section of a bicycle inner tube and slip it over the grip. You'll be surprised at the hand control it gives.
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That's a pretty clever idea, Bill. I can see that working really well. The grips are a bit small (for me) and sometimes a little "rough around the edges". Thanks-
Wyo
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Gary, I definitely recommended removing the RH grip and lightly sanding the edges where the 2 grips meet. I use either 1000 or 1500 grit wet/dry. It's takes all the scratchiness away and it's not noticeable at all. I sand away a lot of the other casting flash that way also.
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Thanks, Tom. I'm going to do that the next time the .177 cal is open and hit the .22 cal (work-in-progress) right now... they're both not so good.
Wyo
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Gary, I definitely recommended removing the RH grip and lightly sanding the edges where the 2 grips meet. I use either 1000 or 1500 grit wet/dry. It's takes all the scratchiness away and it's not noticeable at all. I sand away a lot of the other casting flash that way also.
Great idea, but I might add that you should probably use a sanding block, just to ensure a straight edge. 3M makes an excellent block. I have spent many thousands of hours pushing them to and fro on automobile bodies!
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I just found the grip slippery. The inner tube slip on resolves this.
This was not originally my idea. I kinda stole it from someone here.
I just found it to work really well.
I think I also read somewhere that a Glock style slip on fits as well.
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I just found the grip slippery. The inner tube slip on resolves this.
This was not originally my idea. I kinda stole it from someone here.
I just found it to work really well.
I think I also read somewhere that a Glock style slip on fits as well.
I have a Pachmayr Grip Glove CZ 75/85 on one of my Crosman's. I just tried it on the P17, feels great!
(https://a4.pbase.com/g12/18/442518/2/170294825.RSfKxJbx.jpg)
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That looks terrific, Rick. And I'm going to bet that it has a nice feel like you said.
What we'll do for a 30 dollar gun, lol... oh wait... it was $7.50. :o Thanks-
Wyo
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Very nice detail work Gary!
Following!
I was just gifted a P17 (Thank you Phil) so very interesting thread.
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What we'll do for a 30 dollar gun, lol... oh wait... it was $7.50. :o Thanks-
Haha
I was thinking the same thing when I saw the grip cover. I'm betting that the grip cover cost just as much as the $7.50 pistol.
Wait! Now that I think about it, Amazon is brilliant! Sell a well known good shooter, at a loss, but it has been calculated to make up for the loss, and gain profit via accessory purchases. It's the whole printer, ink market model.
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What we'll do for a 30 dollar gun, lol... oh wait... it was $7.50. :o Thanks-
Haha
I was thinking the same thing when I saw the grip cover. I'm betting that the grip cover cost just as much as the $7.50 pistol.
Wait! Now that I think about it, Amazon is brilliant! Sell a well known good shooter, at a loss, but it has been calculated to make up for the loss, and gain profit via accessory purchases. It's the whole printer, ink market model.
Enter the inner tube cross section... ;)
What? Maybe a $2.99 inner tube at Walmart? .... and it will provide slip ons for all of those 16 guns some of you bought in this $7.99 deal.
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What we'll do for a 30 dollar gun, lol... oh wait... it was $7.50. :o Thanks-
Haha
I was thinking the same thing when I saw the grip cover. I'm betting that the grip cover cost just as much as the $7.50 pistol.
Wait! Now that I think about it, Amazon is brilliant! Sell a well known good shooter, at a loss, but it has been calculated to make up for the loss, and gain profit via accessory purchases. It's the whole printer, ink market model.
Enter the inner tube cross section... ;)
What? Maybe a $2.99 inner tube at Walmart? .... and it will provide slip ons for all of those 16 guns some of you bought in this $7.99 deal.
Nope, still too much money. You need to wait until you come across a free bicycle left curbside. ;)
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Got a spare inner tube that leaked and was filled with slime... hmmm... I'll probably go to Walmart for the $2.99 special. It still leaks btw, lol.
I may have gone beyond the inner tube and grip cover a bit... new barrel (.22 cal) that was cut from a $115 LW blank, and a few hrs machining. Shown with the oem barrel and a fake brake:
(https://i.imgur.com/ayjDoJd.jpg)
It fits! Now I'm going to cold blue the barrel and patiently wait for the other stuff I still "need" ;D
Wyo
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More progress on the .22 cal conversion...
The cold bluing didn't turn out great but I guess it's o.k. for what it is... looks better when the room is dark, lol
(https://i.imgur.com/nfnJi9X.jpg)
This .22 barrel has an o.d. of .480" so some bigger cuts had to be made to the frame...
Muzzle drilled to .484 (31/64"):
(https://i.imgur.com/ou4GtFn.jpg)
Clearance cut was larger too (shown with the .177 for comparison):
(https://i.imgur.com/Hrwez2q.jpg)
Everything else was done the same...
(https://i.imgur.com/CM4nK5q.jpg)
Now I need to find out how fast (or slow) this thing shoots.
Wyo
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Gary, you should go ahead and start building a museum for all your guns. It can be a pilgrimage destination for all of us in awe of your skill. 😁 Maybe go one step further and make a virtual tour for it for those of us gps-ly challenged.
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Thanks, Terry. I have about 32 pistols that survived the various operations over the years and still live today… but had a few that didn’t make it, lol
Found some time to chrony the .22 cal conversion today (when I wasn’t shoveling snow):
jsb 13.73 gr @ 359 fps for 3.9 fpe with an E.S. of 4 fps
So the longer .22 cal barrel, with 80% more barrel volume, is only shooting with 20% more fpe… I’m reaching diminishing returns pretty fast here. At 10m range it punches a pretty decent hole so I’m o.k. with it for now… accuracy tests are still pending.
I guess I did make one minor internal change (to the piston). Not sure if it mattered but the channel was cut in a trapezoidal shape instead of rectangular:
(https://i.imgur.com/H4pWAmT.jpg)
Thanks-
Wyo
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Using your recipe Gary, my P22, using a 1322 Crosman barrel, with JSB 13.4 gr Diablo Exact is running 373 FPS average, with ES of 4.6 FPS, or 1.2%. 4.15 FPE. For giggles I tried some 15.9 gr JSB's, they slow down to 346 fps average, with 4.23 FPE. There is more kick when I shoot the 15.9's.
Had to hand file the slot in the JB Weld. I didn't bottom the notch down to the aluminum, since the cheap needle files don't have very good teeth on the narrow sides. The file is 0.050 wide, which is close to the hole size. For my P17/22, the JB Weld is 0.025" thick, as the headspace measured 0.027". I left a few thousandths for the cyanoacrylate. Haven't gotten to sealing it yet. I may get a couple of more fps, as I know this o-ring has a nick in it. Planning on sealing the JB Weld and replacing the o-ring soon.
When you cold blue, how do you clean the barrel exterior? Is alcohol sufficient? I need to touch up my barrel, have slight 4 jaw marks on it.
Where do you find LW 22 barrels? Haven't seen many of them lately. My Crosman barrel was a practice run.
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Nice numbers - that turned out well, Bruce.
I started doing these mods with my first P17 (about 7 years ago) because of the anemic performance in the thin air. But none of these mods were my ideas.
What's nice is when you put them all together they make a real difference... enough to make the .20 cal (i.e. Superchikn's work) and the .22 cal a viable option in this platform... again nice job!
I used rubbing alcohol to clean the barrel but I'm no expert... this was my entire procedure:
https://www.gatewaytoairguns.org/GTA/index.php?PHPSESSID=e954948fe94de2ab9cf24294ace04a00&topic=156933.0 (https://www.gatewaytoairguns.org/GTA/index.php?PHPSESSID=e954948fe94de2ab9cf24294ace04a00&topic=156933.0)
I got this LW barrel blank from the Lothar Walther website:
https://www.lothar-walther.com/ (https://www.lothar-walther.com/)
Perhaps you can get them now from Crosman if you have a custom shop gun??? That would be faster and less expensive but I don't have a custom shop gun so I'm not sure. Thanks-
Wyo
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Thanks. Appreciate it. First time on a lathe. You wouldn't believe all the mistakes I made. Fortunately, all the mistakes were recoverable. All I can say is I've put in a lot more labor than the purchase cost! Of course, it's hard to beat $7.50.
Oh, boy, that barrel blue turned out beautiful! Seriously, its stunning. I'll have to try the Ospho blue. Never had much luck with other bluing.
LW isn't giving away those barrels. Ouch. Do they sell shorter barrels than 23"? Didn't see any in the airgun category.
Don't have a CCS gun, myself. Also really don't want a flat spot on top of the barrel, since there's no intent to put on a front sight. On the other hand, a ~$50 option, is better than $115.
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Crosman no longer sells special CCS items even of you have a CCS gun.
Tried it this morning, a trigger shoe among other items, and was turned down.
Probably it depends on who is answering the phone, lol!
Called them to get the prices of 1720T parts.
The pellet tray for it is very expensive at $17 ::)
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I really need one of these P17's ! not worthy, about Crosman CS guns. That's why I bought one!
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Bookmarking for future tinkering purposes.
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Hi
Great pictures! I modified my HW40 a bit over the last year.
-2 seals on the piston
-Trigger
-Removable, adjustable and 3D printed shoulder rest
Next mod will be the barrel. Can someone provide me a part number, and maybe a good shop which shippes overseas, for a 10" .177 barrel I should use? Germany is not the best place to bus Crosman parts.
By the way, where can I find the UC70D 116 seals and updates seals for the transfer port?
Thank you,
Michael
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Hi
Great pictures! I modified my HW40 a bit over the last year.
-2 seals on the piston
-Trigger
-Removable, adjustable and 3D printed shoulder rest
Next mod will be the barrel. Can someone provide me a part number, and maybe a good shop which shippes overseas, for a 10" .177 barrel I should use? Germany is not the best place to bus Crosman parts.
By the way, where can I find the UC70D 116 seals and updates seals for the transfer port?
Thank you,
Michael
For barrels:
https://mellonair.myfreesites.net/faqs (https://mellonair.myfreesites.net/faqs)
http://www.alchemyairwerks.com/store/c1/Featured_Products.html (http://www.alchemyairwerks.com/store/c1/Featured_Products.html)
https://alliancehobby.com/index.htm (https://alliancehobby.com/index.htm)
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Thank you for the feedback.
By the way, i managed to attach some pictures. This is my HW40:
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Last mod – Piston
This shows the original piston (minus cheap oem o-ring):
(https://i.imgur.com/Fntl8rO.jpg)
The mark on the piston is how far it comes out of the cylinder at the end of the intake stroke… that established the location for the back of the oil wick groove.
Groove is cut .120” deep and .250” wide:
(https://i.imgur.com/hcoVaNZ.jpg)
The felt is .125” thick F-3. Cut to 5/16” wide it was a really tight fit in the groove:
(https://i.imgur.com/rwajgMk.jpg)
Last thing is the now famous “diametrically channeled shim”… and a better o-ring (UC70D 116):
(https://i.imgur.com/fx4xYiX.jpg)
(https://i.imgur.com/QGWdsmL.jpg)
The shim is .033” thick JB Weld and coated with cyanoacrylate.
All this for a pistol that cost $7.50…
(https://i.imgur.com/FFKvq3C.jpg)
(https://i.imgur.com/2CI7Jec.jpg)
Wyo
Hi Wyoman, thank for posting these great mods! Do you think the piston head channel mod would work if you'd make a channel in the valve face instead?
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Thank you WyoMan
This is an excellent write up with all the clear text and pictures!!!
Regards
Ray
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Nice work as always, Wyoming!
Sorry if I missed it, but what is the purpose of the channel on the piston face?
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2k1TJ - If I understand this correctly, the channel on the piston face allows any compressed air a path of least resistance when the trigger is pulled and the valve opens.
I am new to the P17 and have only had mine for a little over a month. I love the gun so much that I've already followed this guide and done the longer barrel, piston and o-ring mods. I intend to make mine backyard friendly with a moderator, but do not yet know how the moderator will effect my ability to open/extend the piston completely. I used a Crosman barrel on my build, but just recently learned about the Lothar Walther choked barrels, and may consider upgrading again in the future. I really like the idea of building a carbine but am not entirely willing to give up the maneuverability of a pistol. My P17 was purchased as a primary form of mouse control, so I need to be able to maneuver it easily while peeking out the window.
The next upgrade for me will be adding additional weight to the handle. With my red dot reflex sight and the thicker Crosman barrel I can see the need for it to be balanced.
I hope I haven't missed the hay-day of the P17, as it seems there were quite a few enthusiasts at one point and I hope to connect with you all soon.
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Joe, that is correct.
There is compressed air on the piston side of the bulkhead (mainly around the o-ring gland). The channel aligns with the bulkhead port so the compressed air on the piston side can flow thru the port and contribute to the firing charge.
And,,, Thanks guys! :D
Wyo
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I would like to do the longer barrel mod - I have a 1377 10" barrel 7/16" OD.
I already did the Tom Tucker piston and several of WYO's 5 simple mods.
I have a drill press but no lathe.
Is it practical to use the drill press with emery sand paper to do the first reduction to .395" OD and then a small file to do the second to .315" OD
WYO's pic is what I am looking at.
Thanks, Robert
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Hi Robert,
I can't answer about the drill press idea (never tried it), but there might be some concern about lateral loads on the bearings.
However,,, determination, perseverance, and innovation can get a fellow results. My first few barrel blanks were turned with this contraption:
(https://i.imgur.com/wJVn3NS.jpg)
(https://i.imgur.com/xXddBPB.jpg)
It got a few laughs and was later called the "Twin File Lathe", LOL
The swarf was pretty unique:
(https://i.imgur.com/YxyU9SM.jpg)
First attempt turned-out (pun :D) pretty well:
(https://i.imgur.com/3JhtCmd.jpg)
Thanks-
Wyo
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WyoMan, your "Twin File Lathe" is genius!
I can not tell from the pics, are the nuts and threaded rod attached to the file, if so how? Am I assuming correctly that the nuts need to be the same as your desired final OD of the work piece (or a wee bit smaller assuming you can shim them to final size)?
Sometimes when I think I am clever, I see things like that and say, nope, I'm on the wrong side of the bell curve.
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I am giving this a try - both WYO's twin file and just a single file.
Turning the barrel in my drill press.
Started at .435" dia - down to .430" - this is going to take a while to get to .395".
Then reducing area to .315" and cutting off breech end.
Into to it now - continue or give up is the question ?
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Dive in! You've stuck your toes in the water.
Seriously, you made the big step. Now it just takes some perseverance. It will turn out great!
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Robert, I'm not recommending this to anyone. It was just an example of what could be done.
Please use caution, make sure your hands can clear any trouble, make sure you're ready on the kill switch, and yes,,, perseverance is necessary as well as keeping the files wet with WD-40, an old toothbrush to clean the files constantly, and perseverance... guess I said that already...
Wyo
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I did think of using a light oil but the forgot to use it.
Thanks, I will try WD40 and may be still working on it in 2021
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I too used a drill + file = lathe method very similar to Wyoman's. Worked very well on my first attempt. Lateral movement was an issue, but I used a notched board to hold the barrel in position while I took material off.
Now that I have a better idea of what I'm doing I suspect my next barrel will be quite nice.
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For anyone going at it with the file method I should add, it does take a long time. Like, all morning long.
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Good idea about the notched board - thanks for the help.
I just tried drilling a 7/16 hole thru a 2x4 for a bottom guide - works real good.
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There you go, guys... that's the innovation part... Kudos!
WyoMan, your "Twin File Lathe" is genius!
I can not tell from the pics, are the nuts and threaded rod attached to the file, if so how? Am I assuming correctly that the nuts need to be the same as your desired final OD of the work piece (or a wee bit smaller assuming you can shim them to final size)?
Sometimes when I think I am clever, I see things like that and say, nope, I'm on the wrong side of the bell curve.
Hi Wepster, sorry I missed this earlier...
The threaded rods were tie-wired onto the files.
And yes, the flats across the nuts (in the example shown) measured 7/16" nominal which was diameter I needed. But it leaves it about 5 thou oversize.
BTW, the 5 thou oversize is perfect for finishing with sandpaper using a "check and chase" to the part it has to fit... and the sandpaper leaves a nice finish... hth
I have since moved on but will still do caveman machining from time to time, LOL... the early years
Wyo