GTA
All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Topic started by: mackeral5 on November 11, 2020, 12:24:15 PM
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While waiting on parts to put this set of parts in its final form, I assembled it into something semi-useful. A little long for a pistol, but not much longer than a Prod. weighs in at a hefty 3.5lb
(https://i.imgur.com/DQ1UOxZ.jpg)
B&A "thirty plus" breech, added bolt handle, converted to 10/32 cocking lug
16" TJ's 1/26 sleeved in 16mm CF
Cothran valve modified to simplified balanced valve format
Prod trigger w/Airgun Lab sear
Gen 1 Brod tube of unknows manufacture
Hogged out and plugged OEM gauge port
Medium weight MDS hammer of unknown manufacture
Home made twin-spring setup
Filled to 2800psi and 81gr pellets, 3 shots
762
787
753
Ends at 1800psi.
130gr slugs peak at 540fps across 3 shots. 158gr peaks at 450fps.
Long term this will have a shorter tube with no gauge block, 350cc bottle, and an AR style collapsible stock. Just waiting on the tube and stock adapter.
Until then, I would like to use it as a pistol but do not have a sight/scope. Can anyone please recommend an economical solution?
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That's purty!
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Great job! Good numbers
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8) 8) 8)
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Hey Mike
Sharp looking handgun............ ;)
I don't know what the recoil flip is, but have you thought of adding a Gill type muzzle break,
It would greatly reduce the bbl flip and felt recoil etc.
https://rossbrakes.com/about
I run a 5 gill on my 284 pistol 18" bbl with a 5 -15 x rifle scope, and don't get scope bit........ now, LOL
Don
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I have not tried these yet but they have good reviews, I see a sale I may have to get one too.
https://www.seeallopensight.com/ (https://www.seeallopensight.com/)
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Nice looking pistola; some pretty serious power, too! I hope you can find some sights, that's too much gun to have to sit on a shelf because you can't aim it :(.
Good luck,
Jesse
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Thanks for the kind words.
Don--Regarding muzzle flip, it does have a bit. You had previously shared Ross's info and I bought one of his for another project. I will be gluing on a 16mm× 1/2-20 muzzle adapter, may as well pick up another one of Ross's brakes. Thanks for pointing that out.
I am leaning towards an entry level scope from Simmons, BSA, UTG, etc, but I really hate the concept of trying up $100 in an optic that I may only briefly use.
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I decided to bite the bullet and pick up an entry level handgun scope, the BSA 2-7 x 28mm Edge. Hopefully it will work well..
Today I also had the opportunity break from work and exchange a nitrogen cylinder, so now I can get full fills. This little hand cannon wakes up a bit with a 3000psi fill. I had to dial up the hammer spring a bit as the first shot at 3000psi was only 682fps.
Now 3 shots of 81gr pellets goes 807, 810, 782
the scope should arrive next week and I can demonstrate how poor of a pistol shooter I am. In carbine form this gun easily shoots under an inch at 50 yards. I'm betting I will not be able to get under 4" as a pistol, lol....
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The scope arrived yesterday, I found a set of rings that appear to be close enough so I mounted the scope.
(https://i.imgur.com/5JFYcPu.jpg)
Over recent days I've done some more testing which involved several different configurations which I plan to organize the data and share it later. The most recent configuration involved converting the valve back to Powerhouse format by reinstalling the rod in the poppet stem. I also run these valves in Simplified balanced valve format by removing the rod and replacing the seal material with delrin. Note do not remove the rod of your Cothran Powerhouse valve unless you replace the seal material with something harder such as delrin. Your OEM seal will be destroyed running without a rod as it is too soft.
Porting is at .290, valve throat .350. 47gram hammer. 16" barrel.
In Simplified Balanced Valve format a 2900psi fill produces 5 shots 778, 787, 792, 772, 738 with 81gr pellets, ending at 1700 psi.
In Simplified Balanced Valve format a 2900psi fill produces 3 shots 533, 540, 521 with 130gr slugs, ending at 1600psi.
In Cothran Powerhouse format a 2900psi fill produces 3 shots 827, 797, 742 with 81gr pellets, ending at 1600psi. Max 123fpe on pellets
Also in Powerhouse format a 2900psi fill produces 3 shots 689, 637, 569fps with 130gr slugs, ending at 1600 psi. Max 135fpe, not too shabby for a hand cannon.
These results are in alignment with my previous Cothran testing.
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Whew! Beauty!
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Super cool, looks like fun
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So far it has been interesting. I've never shot a scoped pistol until now. At least from a rest it isn't quite as difficult as I imagined.
It is LOUD though. Loud enough that out of respect for neighbors I won't shoot successive 3 shot strings. Shoot a string, give it a break for a few minutes, shoot another. Have a threaded adapter on the slow boat from Poland so I can mount a Ronin.
While I am glad I am able to get some use out of the gun in its current state, I really am looking forward to it's final form as a sub 7lb lightweight, 350cc, 150fpe BLASTER.
This is a pic where I mocked it up a few months ago. Imagine this gun, but with a tube short enough that the tank block butts right up against the valve. The 350cc tank will end 1.5" or so rearward of the Ronin.
(https://i.imgur.com/Qtdtosn.jpg)
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I like the bell curves with the simplified balance valve with delrin seat configuration. :) Much better efficiency with the pellets, too.
Did you have the poppet stem hole opened for both configurations?
PS: I hope to get back to my PH valve testing in a couple of weeks.
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I like the bell curves with the simplified balance valve with delrin seat configuration. :) Much better efficiency with the pellets, too.
Did you have the poppet stem hole opened for both configurations?
PS: I hope to get back to my PH valve testing in a couple of weeks.
The stem vent has been slightly enlarged and the same stem used in both valve configurations. I have a stem with a larger vent that produces lower velocity/greater efficiency, but if you try to over-drive it with HST to get the velocity beyond where it wants to run efficiency falls off. IIRC the vent is around .025. I think I'm going to convert the valve back to SBV format. It was fun to run it WFO for a while, but I would like to tone it down a bit for target shooting. It doesn't take much energy/velocity to punch paper at 30 yard....
I look forward to seeing how your testing goes.
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This particular gun has a bit of modularity designed into it that will support a fairly broad range of configurations. As pictured above, it is a 60cc tube, 16" barreled large pistol or with a stock mounted it is a short carbine. By screwing in an Mrod tube extension it becomes a ~130cc tube. Barrels can be swapped from 16" to a 21". These changes can be made pretty easily, without having to separate the breech nor trigger assembly from the tube. There is also another variable in how the valve is setup to run---either as a Powerhouse, in the format Don Cothran designed it to run, or as a Simple Balanced Valve (SBV), a configuration that I have done a lot of testing with. In the gun's current state, due to having a gauge port, toggling between PH and SBV configurations requires full disassembly.
What are these 2 valve configurations? To put it very simply in Powerhouse format it is pretty much a max power effort with efficiency being a bit of a secondary priority and a bit of a challenge to obtain. In SBV configuration it becomes a mid power level valve that is easy to open and closes fast, thus is pretty efficient. Each valve configuration has its own unique tuning nuances. I sum it up as PH is great for slugs and heavier weight projectiles, SBV is better for pellets and lighter weight projectiles. These are merely my opinions based on my personal experience and preferences. YMMV.....
I put together some charts showing PH vs SBV valve configurations, with different length barrels and air tubes. 81gr pellets were used for all testing. Hammer weight, HST settings, and porting are identical for all configurations. All strings have a starting pressure of 2900psi. Porting is .290. Hammer is an MDS hammer with a total weight of 47grams including striker and cocking bolt.
First up, the gun as pictured. 60cc tube, 16" barrel. Orange line is Simple Balance Valve configuration, blue is Powerhouse.
(https://i.imgur.com/aJhTmHb.png)
Next up, 60cc tube, 21" barrel. Orange line is Simple Balance Valve configuration, blue is Powerhouse.
(https://i.imgur.com/5zlxIVR.png)
Now let's add the tube extension, effectively increasing air storage to 130ish cc.
Here is the 16" barrel. Note in this chart you can see a flatter than typical PH string, this is right on the edge of not having enough hammer strike to open the valve properly. This is due to the larger capacity maintaining a higher average pressure during the shot. With more hammer energy the first shot would have shown a bit more FPE, likely upwards of 135fpe.
(https://i.imgur.com/Qp2R27j.png)
Here is the 21" barrel. Again, orange line is Simple Balance Valve configuration, blue is Powerhouse.
(https://i.imgur.com/3eH07kT.png)
Again note the atypical start to the PH string, more hammer strike would have likely pushed this shot up to the 158fpe range.
In this 21" barrel, 130cc tube configuration, simply switching ammo and lugging it down with 158gr will generate 185fpe.
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That is some phenomenal work!!
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That is some phenomenal work!!
Thanks Tom. I've previously made multiple statements around running the Cothran in this alternative SBV configuration, the intent here was to use real world data to compare the configurations. This shows with a fairly straight-forward modification the Cothran can be a bit more versatile in higher FPE applications. The short tube data shows a good job of what could be expected in a B'rod, peak velocities occurred around 2500psi...
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I have not tried these yet but they have good reviews, I see a sale I may have to get one too.
https://www.seeallopensight.com/ (https://www.seeallopensight.com/)
I tried their 1st gen sight on a pistol and it was unusable for me. Too hard to line up the reticle/lens. Works okay on a rifle, though.
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I have not tried these yet but they have good reviews, I see a sale I may have to get one too.
https://www.seeallopensight.com/ (https://www.seeallopensight.com/)
I tried their 1st gen sight on a pistol and it was unusable for me. Too hard to line up the reticle/lens. Works okay on a rifle, though.
Thanks for sharing your experience.
I looked at those and didn't want to roll the dice on something unknown to me. While I have no previous scoped pistol experience, I was familiar with tubes/lenses/crosshairs so I somewhat knew what to expect when I decided on the entry level BSA piece. In the end I think it was a good choice for my purposes.
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My LDC adapter arrived from Poland yesterday. I made slight modifications to it to accommodate the .357 caliber then cleaned the ID of it and the OD of the CF barrel sleeve with acetone. I coated both with a light coat of Loctite 680, then slid the adapter onto the barrel. after curing overnight the 2 are joined as one.
I now understand why some Crosman pistol owners affectionately refer to their guns as Lego guns. The possibilities are endless.
Here I've configured this as a 8lb 3oz, 45" , truly BACKYARD QUIET 115fpe little monster. This is very close to what I have planned as the final configuration....I think.
(https://i.imgur.com/MSwzZAx.jpg)
I had the valve apart earlier to convert from PH back to SBV configuration. Here is a pic showing the poppet with delrin valve seal and slightly enlarged stem vent.
(https://i.imgur.com/Wi2l1WT.jpg)
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That gun is way cool Mike !!! That's what I should do with my Gen2 Mrod, at the moment it's been in limbo for quite some time now, I never did like the barrel that came with the gun to begin with (Green Mountain).
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Which LDC did you go with?
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Which LDC did you go with?
I have an emperor and a ronin with extensions. The picture shows the Ronin/extension combo. Both of my large Neil C units are reflex, slip on type so they won't fit this gun. The Emperor does well, but not quite as good as the Ronin/etension combo. I haven't run the Emperor w/extension, one can only assume it gets even quieter...
I made some valve adjustments that have quieted it down even further. The adjustments are basically doing my best to mimic Bob's Simple Balance Valve that he described developing for his Hyabusa build----key elements are .056ish vent, .125 stem protrusion from valve, balance chamber adjusted to just barely deeper than full valve lift. Had to go to an OEM (a little over 70 grams, IIRC) due to closing forces becoming so great. The valve is much more adjustable with HST prior to these changes it "wanted to run where it wanted to run", so to speak, with very little room for HST adjustment....more to come...
I'll post some data after I have a chance to organize it, perhaps over the holidays.
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That gun is way cool Mike !!! That's what I should do with my Gen2 Mrod, at the moment it's been in limbo for quite some time now, I never did like the barrel that came with the gun to begin with (Green Mountain).
Thank you Wayne. So far I am liking my first Marauder. Currently in the 220cc brod carbine configuration it is doing roughly 10 shots 765-800-760 with 88gr slugs.
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I now understand why some Crosman pistol owners affectionately refer to their guns as Lego guns. The possibilities are endless.
That is a blessing along with a curse. ;)
The curse being, you will always find another config you want to try. :)
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That is a blessing along with a curse. ;)
The curse being, you will always find another config you want to try. :)
It's more of a curse... ;D ;D ;D But a fun curse!
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My Chrosman Lego kit has been put through many configurations since starting this thread. I spent some time testing a regulated .357 Brod with the 21" barrel. I did a caliber change with a Green Mountain .25 barrel, this yielded some interesting results. The GM was cut down to 18.25", removing the choke. 850fps 34gr JSB pellets running efficiency numbers over 1.6, reg'd at 2000psi. Dialed up to 3000psi they ran 1065fps. Anyway, that's a thread in itself.
Another I learned a cool thing about the Gen 1 platform is caliber changes are simple--- remove the barrel, remove the cocking lug from the bolt, swap bolts, and install another barrel. SSG's are simple to set up and tune as they can be removed without disassembly. I really wish I would have started my PCP journey with the Gen 1 Mrod platform vs. QB.....
Back to the pistol. The 21" barrel configuration put this kit in a niche that is better filled by my regulated Bulldog. The Bulldog does everything the .357 regulated Brod did, but better and it can be turned up to over 300fpe in unregulated form. So, I decided to take the 21" Mrod barrel and turn it into 2 pistol barrels. a 12.5" and an 8." I don't have the muzzle adapter to finish the 8.5", so it is still a work in process. The 12.5" is complete. When all is said and done I will have a 16" carbine, 12.5" big pistol, and 8.5" pistol barrel for this particular Lego set.
Here's a picture of the 12.5" barrel configuration.
(https://i.imgur.com/4udEZi7.jpg)
I also added an SSG, which is still under development--it is functional but not in its final form. With the 12.5" barrel it gives 4 shots of JSB 81gr pellets 695, 710, 715, 690fps. With the 8" barrel it gives 4 shots 632, 655, 645, 630fps. There's still room for fine tuning but this is close to where it will stay.
I'm not the best shot with a pistol, but here is an obligatory 3 shot group at 20 yards, from a rest.
(https://i.imgur.com/nXXEYlm.jpg)
Once I have the short barrel finished I'll update the thread.
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Looking good, Mike. 8) 8) 8)
A nice powerful pistol.
Are you using the JSB or maybe those red ringed slugs that worked in the BD?
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Looking good, Mike. 8) 8) 8)
A nice powerful pistol.
Are you using the JSB or maybe those red ringed slugs that worked in the BD?
Thanks John. Testing so far has been with JSB's. The 88gr HP's from GT bullets would likely run 25fps or so slower. i am running low on them and have an order in but GT Bullets has a crazy 90 day backlog right now---I likely won't see that next order until late Jan/early Feb. Based on previous testing the 88gr should do fine with the shorter barrel/lower velocities. Penetration is a different story..... at 915fps, the 88gr slug expands to almost nickel-sized, and gets trapped in the second gallon jug of water. At 700fps, they pass through 2 jugs of water....
The .25 testing I referenced---I learned a lot there, will share whenever you're ready to do more Cothran testing......
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That's some backlog, but doesn't sound like there is much benefit to them given the velocity.
Yea, I know. ::) I do have to get back at it. Certainly, will share notes. :)
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That's some backlog, but doesn't sound like there is much benefit to them given the velocity.
Yea, I know. ::) I do have to get back at it. Certainly, will share notes. :)
IMO, benefits of the 88gr GT bullet are 2 fold.
Price
Call it $81 shipped for 500 JSB's
(https://i.imgur.com/2cEv2lG.png)
Call it $59 shipped for 500 88gr GT Bullets. Even though they say .356, they measure at .3575-.358 when ordered unsized/unlubed/as cast.
(https://i.imgur.com/nMNQkNq.png)
Accuracy.
The top left is a 4 shot group of as-cast, unsized/unsorted GT Bullets 88gr. The other 4 groups were shot with 81gr pellets. I see the difference in accuracy across all 4 of my .357 barrels, with the 88gr getting the better of the 81gr in each instance. All are TJ's 1:26 barrels. This could have something to do with my barrel prep? I don't know . Barrel port is .280 wide so I do not think it should be affecting pellets, but maybe that is it. Either way I feel more confident in the GT Bullets 88gr HP over the JSB 81gr pellets.
Note targets were shot in the following order, with scope adjustments in between groups of 4. Center (3 shots), top right, bottom right, bottom left, top left being the last group. Refilled from 1800psi to 3000psi between groups.
(https://i.imgur.com/mwYDRKU.jpg)
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That is impresive.
If I recall correctly, they shot well out of your BD barrels, as well. I think that is how I ended up with a sample pack. ;)
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Ah, beauty!! You got a link for those 88 gr. slugs? All I'm seeing is 115 gr on up. Also, what alloy are they using? Or is it pure lead?
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Ah, beauty!! You got a link for those 88 gr. slugs? All I'm seeing is 115 gr on up. Also, what alloy are they using? Or is it pure lead?
https://www.gtbullets.com/index.php?main_page=product_info&cPath=10&products_id=31 (https://www.gtbullets.com/index.php?main_page=product_info&cPath=10&products_id=31)
Supposedly 2-2-96. I have no knowledge to interpret those numbers. What I can tell you is they FULLY expand and get stuck in the second gallon jug of water at 60 yards, with a muzzle velocity of 915fps. They must not be too hard....
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In post 27 I failed to include any data around the hammer system. For that testing I was using an OEM hammer weighing in a little over 75 grams and a fairly stout spring in the SSG. Previously I was shooting slugs with the longer barrels so the extra dwell was needed. The spring is from McMaster Carr and is .055 wire stainless. I don't have the specs, but it is much heavier than an OEM QB78 spring, for example. Cocking effort not uncomfortable, but fairly significant.
While digging through my excess junk I found a spring I ordered back a couple of years ago when NVreloader/Don was posting about the merits of flat wire springs. It is a 20lb spring for a 5 " full sized .45ACP running +P loads, part number 614620. I checked compressed height and it will indeed fit my SSG.
I put the light 47 gram hammer back in and put the flat wire spring in the SSG. After a bit of testing I found this string and repeated it a few times.
JSP 81gr, 3000psi to 1500psi
653, 657, 664, 661, 678, 685, 672, 649fps.
8 shots averaging 664fps (79fpe) out of ~60cc of air and a 12.5" barrel.
Also, all of the things Don previously said about flat wire springs were finally proven true to me. it is a lot easier and buttery-smooth to cock this thing now....
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I'm probably wrong, but 2-2-96 could be 2% tin, 2% antimony 96% lead... If this is the case, it should be fine for airgun use.
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I've spent some time now practicing my pistol shooting. I am "cheating"---shooting from a well-rested position. However shooting accurately without a shoulder stock is something new for me. it also helps that a Ronin is installed (to be more respectful of our neighbors) but it also helps keep things stable.
I stretched a target out to 50 yards to demonstrate the valve's functionality. Remember this is a Cothran Powerhouse valve, with a modified poppet. Touched off by a 47gram hammer and reasonable cocking effort. 8 shots of JSB 81gr running right at 80fpe. Not tethered, shot from a full fill. 3000psi fill shot down to 1200-1500psi on a ~60cc reservoir. Remember there is a gauge block in there consuming valuable space....
A pic with the Ronin.
(https://i.imgur.com/EXb0ab7.jpg)
A pic of the shooting position.
(https://i.imgur.com/3H6EqFM.jpg)
The target---again 8 shots at 50 yards. Same point of aim for all 8 shots. This group was not cherry picked, it is the first and only 50 yard group I have shot with this gun and I'm a relatively new pistol shooter.
(https://i.imgur.com/GxjAX9T.jpg)
I didn't quite position my target properly so an oak tree suffered a little damage. I shifted the target over a bit to prevent further damage. I couldn't help but marvel at the damage inflicted by a "pellet pistol" at 50 yards.
(https://i.imgur.com/MMdgxNz.jpg)
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Excellent group for for 50yd, especially on first attempt! WOW!
Eight 80fpe shots! You have me rethinking 357 in a pistol. Didn't think that was possible. I think CARM needs a 25/35 mag! ;)
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Most Impressive!!
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-Mindblown- 8) 640-ish total FPE out of a 60 cc tube with a 12" barrel??? That is simply amazing; thank you for putting out all the details on the build so others can learn from your achievements.
Just cooooooooooooooooool, :D
Jesse
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Excellent group for for 50yd, especially on first attempt! WOW!
Eight 80fpe shots! You have me rethinking 357 in a pistol. Didn't think that was possible. I think CARM needs a 25/35 mag! ;)
Thanks John. It was really a communal effort, whether others knew they were actively participating or not....
Bob gave us the SSG I think he also partnered in developing the TJ's .357 1:26 that is used for all 3 barrel lengths this gun has.
Don/NVreloader introduced me to the flat wire spring
Scott/Motorhead pioneered ultralight hammers and openly shared a lot of balanced valve design and tuning data.
Then you have the group of folks that contributed to the Simplified Balanced valve thread.
The only piece I will take specific credit for is being hard-headed enough to get the Cothran to shoot a bell curve, across a broad pressure range. Even though I was simply mimicking the efforts of those listed above.
Next, I believe I will make a .25 caliber change kit using a cut down GM barrel and the .22 bolt/breech you sent me....I think I will make an entire top end so I can use magazines.
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Excellent group for for 50yd, especially on first attempt! WOW!
Eight 80fpe shots! You have me rethinking 357 in a pistol. Didn't think that was possible. I think CARM needs a 25/35 mag! ;)
Thanks John. It was really a communal effort, whether others knew they were actively participating or not....
Bob gave us the SSG I think he also partnered in developing the TJ's .357 1:26 that is used for all 3 barrel lengths this gun has.
Don/NVreloader introduced me to the flat wire spring
Scott/Motorhead pioneered ultralight hammers and openly shared a lot of balanced valve design and tuning data.
Then you have the group of folks that contributed to the Simplified Balanced valve thread.
The only piece I will take specific credit for is being hard-headed enough to get the Cothran to shoot a bell curve, across a broad pressure range. Even though I was simply mimicking the efforts of those listed above.
Next, I believe I will make a .25 caliber change kit using a cut down GM barrel and the .22 bolt/breech you sent me....I think I will make an entire top end so I can use magazines.
Agree 100% on all the people that have contributed to the GTA forum. :) I wouldn't minimize your work, especially getting a bell curve with PH valve. You share all your projects, successes and problems you run into. It is much appreciated.
I don't want to think much on a 357. Well, I do, but need to focus on getting the 30 cal done. ;)
PS: I do need to look into those flat wire springs.
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For those interested in flat wire springs, here is a selection for you to browse:
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2499334.m570.l1313&_nkw=flat+wire+springs&_sacat=73944 (https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2499334.m570.l1313&_nkw=flat+wire+springs&_sacat=73944)
FYI,
Full length spring are around 5" total overall length,
Commander springs are around 4" total length,
Officer springs are around 3",
Plus there are lots of spring for Glocks etc,
Ask the seller for length, O/S diameter and I/S hole diameter if you plan to run a spring guide etc.
I know a 5" Full length flat wire spring goes coil bound in 1.030".
If you are using these springs, use full length, then cut to fit etc, they are NOT like round wire springs..........
;)
HTH's,
Don
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I may have to experiment with flat wire springs for both my .357 Brod, and my Bulldog builds!!
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The spring i previously is almost perfect for Mrod use as well as the type of SSG I use in my QB/Gauntlet builds.
Something I learned along the way is use as many coils as you can, the full spring will fit in a Gen1 Mrod. I made the mistake early on of cutting the flat wire spring too ahort.....
It is amazing to encounter a constant, steady resistance when cocking vs cocking effort increasing as you get closer to latching the sear.
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For those interested in flat wire springs, here is a selection for you to browse:
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2499334.m570.l1313&_nkw=flat+wire+springs&_sacat=73944 (https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2499334.m570.l1313&_nkw=flat+wire+springs&_sacat=73944)
FYI,
Full length spring are around 5" total overall length,
Commander springs are around 4" total length,
Officer springs are around 3",
Plus there are lots of spring for Glocks etc,
Ask the seller for length, O/S diameter and I/S hole diameter if you plan to run a spring guide etc.
I know a 5" Full length flat wire spring goes coil bound in 1.030".
If you are using these springs, use full length, then cut to fit etc, they are NOT like round wire springs..........
;)
HTH's,
Don
Thx, that helps some. I did do that search on ebay, amazon and elsewhere, yesterday. I guess I am spoiled by McC with having all the OD, ID, length, spring rate, max load, and coil bind data available. ;) I only found the ones made for specific guns and places that will custom make them. I didn't start requesting the data from the suppliers, yet.
Mike, Do you have a pointer to the one you purchased? Might save me some trial & error headaches.
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I just bought one of those flat-wire springs. They're recoil springs for 1911's. Part number is: 614G20. Here's the ebay link:
https://www.ebay.com/itm/Wilson-Combat-1911-Flat-Wire-20LB-Recoil-Spring-5-Full-Size-45-ACP-P/231789667525?hash=item35f7bda4c5:g:C~oAAOSwUdlWdtWZ (https://www.ebay.com/itm/Wilson-Combat-1911-Flat-Wire-20LB-Recoil-Spring-5-Full-Size-45-ACP-P/231789667525?hash=item35f7bda4c5:g:C~oAAOSwUdlWdtWZ)
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I just bought one of those flat-wire springs. They're recoil springs for 1911's. Part number is: 614G20. Here's the ebay link:
https://www.ebay.com/itm/Wilson-Combat-1911-Flat-Wire-20LB-Recoil-Spring-5-Full-Size-45-ACP-P/231789667525?hash=item35f7bda4c5:g:C~oAAOSwUdlWdtWZ (https://www.ebay.com/itm/Wilson-Combat-1911-Flat-Wire-20LB-Recoil-Spring-5-Full-Size-45-ACP-P/231789667525?hash=item35f7bda4c5:g:C~oAAOSwUdlWdtWZ)
That's the one, a 20# spring.
I will likely pick up another of the 25#er's to try in my Bulldog's SSG.
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Flat wire springs are amazing, my last two builds cut about 30% off max cocking effort for the same hammer energy with nothing other than a change to flat wire.
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Thx guys for the link and confirmation. It happened to be one of the few I put on the watch list to get more info on. Going to order it. :) Thx again.
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I finished prepping the muzzle of the 8.5" barrel this morning. I am running very low on ammo so I decided to test with some 110gr slugs from Desperado Cowboy Bullets. I've never had much success with these, so I figured why not use them. I ran a dozen or so through the .357 NOE sizer. Then put a few over the chronograph without any SSG adjustments and found them to start around 460fps and peek a little over 500fps. It is terribly loud with no LDC. While I do plan to mount a muzzle adapter and a removable muzzle brake, and I may make up a small extension to be able to install an LDC. The length of this barrel is slightly too short, this is not by design. it was simply a matter of priorities when dividing a 21" barrel into 2 barrels. This is all that was left.
(https://i.imgur.com/lc1ozu4.jpg)
I pulled my target back in to 20 yards and took a sighter, which was high and to the right. I guessed at a pretty extreme elevation and a slight windage adjustment and fired off a shot. It was close enough to do a 5 shot group.
(https://i.imgur.com/W9C8IX9.jpg)
Have I mentioned this thing is LOUD? The sound is a very sharp CRACK, it sounds almost like shooting a small caliber PB pistol. If it weren't so loud I would stretch it out to 50 yards. My ears are still ringing, should have worn hearing protection.....
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I bet it was LOUD! :) My experience with that tube length, a 10" barrel is about right. How's the jump?
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I bet it was LOUD! :) My experience with that tube length, a 10" barrel is about right. How's the jump?
It was surprisingly easy to shoot, compared to what I was expecting.
I chose the 12.5" length for a future configuration, remember the current tube is going to be replaced. it isn't always going to be a pistol, either. Try to picture this combo: 12.5" barrel w/ Ronin, 7 inch tube, 220cc bottle, AR collapsible stock.
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Wasn't sure if that was still the plan. ;) Going to be quite the powerful little carbine. :)
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Wasn't sure if that was still the plan. ;) Going to be quite the powerful little carbine. :)
The short tube is still the long term plan, it just became a little longer term originally thought.
With the 12.5" barrel and 220cc bottle, should be approximately 25-30 shots of 80fpe, call it 34" long including moderator with stock fully extended, around 30" collapsed. Then there are the options of a 16" or 8.5" barrel. The 16" barrel will allow for a 350cc bottle.
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I forgot how short you're going to go!! I thought my carbine was going to be short w/a 18" barrel!!
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Epic build!
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FWIW: I did start a conversation with Darko about a possibility of a Mrod 25/35. I think the mag would be deep enough for the JSB 82g and those 88g GT slugs, but not much more. Should be able to hold 5 shots. Just my eyeballing it. He is going to look into it. :)
I think that having a mag available would solidify what to do with that other short tube, drop block, and .22L bottle. ;)
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FWIW: I did start a conversation with Darko about a possibility of a Mrod 25/35. I think the mag would be deep enough for the JSB 82g and those 88g GT slugs, but not much more. Should be able to hold 5 shots. Just my eyeballing it. He is going to look into it. :)
I think that having a mag available would solidify what to do with that other short tube, drop block, and .22L bottle. ;)
Very cool. I previously measured a jsb .35 vs the thickness of the wheel in Darko's .30 mag, it will work, lengthwise. Note those 88gr slugs I like are shorter than JSB pellets.
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Spent some time lobbing those 110gr slugs at my 75 yard 4" gong. For kicks I put on the Emperor and Extension. Made for an obnoxiously long combo, but it is nearly silent. The 110gr are running around 515fps.
Pfft....wait for it...wait for it....DING. This is more fun that I ever expected.
(https://i.imgur.com/E0tjp4H.jpg)
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So cool!! I can't wait to get mine back together!!
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So cool!! I can't wait to get mine back together!!
That pic was for your benefit, regarding the polish adapters.
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That pic was for your benefit, regarding the polish adapters.
I appreciate it!! I did in fact place an order today. I just wish he made one that wasn't so... squared off. One with a taper like yours would be much better. But I'm not really complaining- this route will be far easier to accomplish!
FWIW: I did start a conversation with Darko about a possibility of a Mrod 25/35. I think the mag would be deep enough for the JSB 82g and those 88g GT slugs, but not much more. Should be able to hold 5 shots. Just my eyeballing it. He is going to look into it. :)
I think that having a mag available would solidify what to do with that other short tube, drop block, and .22L bottle. ;)
Having a mag would certainly be a VERY welcome addition!! I hope this comes to fruition!
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There has been some additional back and forth on the mag, so I'd say he is taking a real look into it.
I have some of those Polish made adapters for 1/2-20, and they do look good with the CF over the barrel, like what Mike has.
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There has been some additional back and forth on the mag, so I'd say he is taking a real look into it.
I have some of those Polish made adapters for 1/2-20, and they do look good with the CF over the barrel, like what Mike has.
A mag certainly would be a fine addition to a .357 converted Mrod, for sure! I may have to build a Gen1 Mrod up myself... Caliber changes would be far simpler...
The tapered adapters do look quite nice over the CF, but the one that I bought, made up for a 18mm O.D. barrel isn't tapered. It's squared off at the back. But on the plus side, I won't have to do a thing else w/the adapter. The through bore is .374". I think a bit of looks is a good trade off for simplicity.
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This is one that is more squared off. I think it looks good with the CF sleeve.
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Oh! That DOES look really nice!!
Silly question- does a Cothran valve interchange between a Gen1 and Gen2 Mrod? Or does the valve have to be generation specific?
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I think that CF was 2mm thick. If using the more typical 1mm, I agree the slight taper would look a little better.
On the Cothran valve, I think the answer is "yes" but would have to go find a picture. Crosman Gen 2 valves work in G1. The differance in the outer body, is just the relief for the trigger assy screw. The G2 valve has a slot, which covers both positions.
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I think that CF was 2mm thick. If using the more typical 1mm, I agree the slight taper would look a little better.
On the Cothran valve, I think the answer is "yes" but would have to go find a picture. Crosman Gen 2 valves work in G1. The differance in the outer body, is just the relief for the trigger assy screw. The G2 valve has a slot, which covers both positions.
The I used 13x16mm CF for this build. With 16" and shorter barrels it is still very stiff. The Polish adapters start becoming squared vs. tapered once you get up to an 18mm ID, IIRC. I have a 17mm on order for another project, it is tapered I believe.
Don's Mrod valves work on both Gen 1 and Gen 2 Mrods as well as WAR Flex and WARP models.
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...Don's Mrod valves work on both Gen 1 and Gen 2 Mrods as well as WAR Flex and WARP models.
That's good to know!!
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I repurposed some parts from other projects that didn't work out the way I wanted and was able to finish the 8.5" barrel with CF sleeve and a muzzle brake.
(https://i.imgur.com/jndhFyu.jpg)
I've found it is very responsive to the SSG. With gap, as one would expect it is very efficient but not performing in the upper end of the energy range I can slightly preload the SSG and get more power, without becoming too inefficient, and pretty flat across 3-4 shots.
Using JSB 81gr pellets with a small amount of SSG gap it does 7 shots 590,596, 600, 610, 615, 605,590. remove the SSG gap and slightly preload the hammer against the valve and it gives 4 shots 662, 667, 664, 642 fps.
That little 4 shot tune of around 75fpe is a pleasant surprise with the short barrel.
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Those are some fine numbers!
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I am still exploring my options, here is another combination of Marauder Lego's.
Remove the Prod trigger, replace it with an Mrod trigger and old beat up stock. Swap the barrel to a 18" GM .25 with the choke cut off, that has been sleeved with CF and one of the Polish adapters on the muzzle. Switch over to a .22 bolt sleeved up to .25 with brass tubing. Add the tank block and 220cc tank. Quiet down with a Tatsu.
All of this is done without entering the power plant nor removing the breech.
After adjusting the SSG, the end result is right at 39" long and produces 35-40 shots of 55fpe with JSB 34gr.
(https://i.imgur.com/9wqcKGw.jpg)
In the end I believe I will build 2-3 guns based on this powerplant, with one being a dedicated .357 pistol. There are 2 key components that are long awaited and will help finalize decision making once they ultimately arrive--an ultra short tube that butts the tank block up against the valve and a custom end cap that accepts an AR buffer tube/stock.
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Yep- that's about what my build will look like, but with a synthetic stock. My tube will be a touch shorter at 10.5", and the barrel is only 18" or so. That'll place the muzzle just past the end of the tank, w/the reg in place. VERY nice build indeed!!
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Yep- that's about what my build will look like, but with a synthetic stock. My tube will be a touch shorter at 10.5", and the barrel is only 18" or so. That'll place the muzzle just past the end of the tank, w/the reg in place. VERY nice build indeed!!
Thanks Tom. Hopefully this thread is demonstrating the potential of Gen 1 Mrods. Once you get away from sealing TP to barrel they become very modular.
Here it is converted back to 16" .357 Brod configuration. Almost exact same length as above--39" with a Ronin.
In this configuration it can be dialed from a bunch of 80 fpe shots to a handful of 130fpe shots by simply adjusting SSG gap....
(https://i.imgur.com/0Mtniyu.jpg)
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I am still exploring my options, here is another combination of Marauder Lego's.
Remove the Prod trigger, replace it with an Mrod trigger and old beat up stock. Swap the barrel to a 18" GM .25 with the choke cut off, that has been sleeved with CF and one of the Polish adapters on the muzzle. Switch over to a .22 bolt sleeved up to .25 with brass tubing. Add the tank block and 220cc tank. Quiet down with a Tatsu.
All of this is done without entering the power plant nor removing the breech.
After adjusting the SSG, the end result is right at 39" long and produces 35-40 shots of 55fpe with JSB 34gr.
(https://i.imgur.com/9wqcKGw.jpg)
In the end I believe I will build 2-3 guns based on this powerplant, with one being a dedicated .357 pistol. There are 2 key components that are long awaited and will help finalize decision making once they ultimately arrive--an ultra short tube that butts the tank block up against the valve and a custom end cap that accepts an AR buffer tube/stock.
You really have that Powerhouse valve and SSG dialed in. :)
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Yep- that's about what my build will look like, but with a synthetic stock. My tube will be a touch shorter at 10.5", and the barrel is only 18" or so. That'll place the muzzle just past the end of the tank, w/the reg in place. VERY nice build indeed!!
Thanks Tom. Hopefully this thread is demonstrating the potential of Gen 1 Mrods. Once you get away from sealing TP to barrel they become very modular.
Here it is converted back to 16" .357 Brod configuration. Almost exact same length as above--39" with a Ronin.
In this configuration it can be dialed from a bunch of 80 fpe shots to a handful of 130fpe shots by simply adjusting SSG gap....
(https://i.imgur.com/0Mtniyu.jpg)
1st, sweet looking lego gun. How are you sealing TP to the barrel and how do swap bolts for cal change without removing the breech?
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Thanks Randy.
I seal the valve to the breech similar to a WAR gun. No need for barrel to breech orings though. Metal barrel to metal breech seals perfectly, just like crosman did with the Bulldog. If it does give a puff of air, a bit of silicon grease on the barrel/breech before insertion is typically enough to seal it.
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Thanks Randy.
I seal the valve to the breech similar to a WAR gun. No need for barrel to breech orings though. Metal barrel to metal breech seals perfectly, just like crosman did with the Bulldog. If it does give a puff of air, a bit of silicon grease on the barrel/breech before insertion is typically enough to seal it.
Mike,
Thanks for the breech seal info! I was hoping it be would be something that I could do on my Prod breeches without much work.
I have extra Prod breeches setup for cal/barrel changes.
Have you thought about launching arrows out of the longer barrel?
Randy
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Thanks Randy.
I seal the valve to the breech similar to a WAR gun. No need for barrel to breech orings though. Metal barrel to metal breech seals perfectly, just like crosman did with the Bulldog. If it does give a puff of air, a bit of silicon grease on the barrel/breech before insertion is typically enough to seal it.
Mike,
Thanks for the breech seal info! I was hoping it be would be something that I could do on my Prod breeches without much work.
I have extra Prod breeches setup for cal/barrel changes.
Have you thought about launching arrows out of the longer barrel?
Randy
You're welcome Randy.
here is a pic of a WAR transfer port on the right and one I made for a Cothran valve in a WAR gun on the left. The WAR unit has orings top and bottom where it seals to the valve and breech.
Believe it or not the brass one I made sealed on the bottom to the Cothran without an oring.
(https://i.imgur.com/VAi5QdF.jpg)
this next pic shows you just how crude my work can be.... The one I use on this particular gun. This is a brass sleeve with 3/8" icemaker line, both are in slight crush when the breech is tightened. the 3/8 icemaker line has been drilled out to .290ish. It ain't perfect but it seals and flows. I have disassembled/reassembled this dozens of times now, with no leaks...
(https://i.imgur.com/y7j5faF.jpg)
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All of my transfer ports are made from poly tubing and get good seals on them, my largest is transfer port is 5/16" OD for the .25 cal mini-rod and the arrow barrel.
I may play around with the brass sleeve though for better support of the poly tubing. Thanks for the tips.
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All of my transfer ports are made from poly tubing and get good seals on them, my largest is transfer port is 5/16" OD for the .25 cal mini-rod and the arrow barrel.
I may play around with the brass sleeve though for better support of the poly tubing. Thanks for the tips.
I started using the brass tubing reinforcement on my QB's where the transfer port becomes exposed and unsupported when you start getting up in size. It seems to work ok for those of us without real fabrication skills/equipment.
I didnt respond to your question about arrows. The airbow concept hasn't quite peaked my interest yet, so I haven't given it much thought. Something about how loud the guns are without an LDC, as compared to releasing an arrow from a bow/crossbow almost silently. I may be wrong but that is my perception of the concept.
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In anticipation of a part arriving next week I converted back to the Prod trigger group and short barrel. Based on the "is it a pistol?" discussions I put the short barrel back on. I rummaged through my junk parts and found an old QB front sight and a random dovetail clamp on rear sight. an ebay 1/8 bspp pressure gauge arrived, so I installed it as well.
(https://i.imgur.com/hUiw9rr.jpg)
Now we have a 3lb 13oz pistol.
in this configuration, adjusting the SSG can vary tunes from a 717, 692, 667 fps 3 shot string to a 619, 636, 650, 641, 624, 606fps 6 shot string with JSB 81gr pellets. There is a longer 500fps tune/string, but once again I find myself out of pellets....
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In anticipation of a part arriving next week I converted back to the Prod trigger group and short barrel. Based on the "is it a pistol?" discussions I put the short barrel back on. I rummaged through my junk parts and found an old QB front sight and a random dovetail clamp on rear sight. an ebay 1/8 bspp pressure gauge arrived, so I installed it as well.
(https://i.imgur.com/hUiw9rr.jpg)
Now we have a 3lb 13oz pistol.
in this configuration, adjusting the SSG can vary tunes from a 717, 692, 667 fps 3 shot string to a 619, 636, 650, 641, 624, 606fps 6 shot string with JSB 81gr pellets. There is a longer 500fps tune/string, but once again I find myself out of pellets....
8) 8) 8)
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A shipment from Canada arrived today....one of the last 2 missing links to this build.
(https://i.imgur.com/4pg3Wk0.jpg)
(https://i.imgur.com/AmR7MJS.jpg)
(https://i.imgur.com/cMGsl1s.jpg)
It wasn't always planned to be a pistol, this is more along the lines of the original intent.
Gippeto made the Gen 1 Mrod buffer tube adapter. It is threaded 1/2-20 all the way through. A very slight interference fit in the tube, absolutely ZERO wobble.
1 out of 2 missing links are no longer missing, still waiting/looking for the shorty tube. Then the puzzle will be complete.
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That's a beauty right there!!! I may have to put out a WTB ad for a Gen1 .25 Mrod! ;D ;D
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He did very nice work on that adapter. :) I might need one for a gen2 tube.
I think that looks allot better vs using the Armada chassis.
Are you still able to use your SSG?
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Hopefully the short tube will come in the next few weeks.... At that point I can fit either the 16" barrel and 350cc bottle or 12" barrel with the 220cc bottle. Toggling between Powerhouse and Simplified Balanced Valve format will only require degassing, removing the barrel and removing the tank block to access and unscrew the piston carrier from the Cothran valve. Then either add or remove the rod from the poppet stem to convert from one format to the other.
I gave Gippeto/Al a very crude drawing with dimensions from a Gen 1 end cap/adjuster that had the degas threads drilled and fully tapped to 1/2-20, and that's what he designed the adapter to. My SSG fit perfectly.
At some point I'll need an AR buffer tube adapter for a Gen 2, but whomever needs one first will have to work through the design with Al. It shouldn't take much to adjust for the additional breech mounting holes and length inside the tube. He is great to work with and does beautiful work.
I waffled back and forth over Prod trigger or Armada chassis for my upcoming Gen 2 build.... The Armada chassis is certainly the less costly of the two. But I think I prefer the simplicity of the Prod trigger and buffer tube adapter....
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If only we had a reliable source for a Prod conversion sear!
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If only we had a reliable source for a Prod conversion sear!
Agreed. It is weird that I was able to order one at the same time you did, my order was fulfilled but yours wasn't....Perhaps they will become a little more organized in 2021???
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The more I look at that short barreled version the more I like it.
The drawing was completely adequate, and Mike was a pleasure to deal with. My schedule makes shop "play" time sporadic, and he was a patient fellow which is always appreciated.
Feel free to shoot a pm when ever you're ready and we can look at the Gen 2.
Regards,
Al
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Agreed. It is weird that I was able to order one at the same time you did, my order was fulfilled but yours wasn't....Perhaps they will become a little more organized in 2021???
I'm glad you caught that- You ordered yours AFTER I did, and actually got them- I never even got an email back... ;D >:(
I can't stop looking at the short version with the AR adapter... I keep thinking about getting a folding adapter and an adjustable stock like this:
(https://mdttac.com/media/catalog/product/cache/772eaea42ae5aaab2a128de135ea6bd1/s/c/scs-family-complete-black_1.jpg)
Combine it w/a AR grip adapter and a precision rifle grip? Oh man. Nice compact little hammer!!
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The more I look at that short barreled version the more I like it.
The drawing was completely adequate, and Mike was a pleasure to deal with. My schedule makes shop "play" time sporadic, and he was a patient fellow which is always appreciated.
Feel free to shoot a pm when ever you're ready and we can look at the Gen 2.
Regards,
Al
Will do. I'll provide info on the "standard" G2 end cap, and what is also needed. In general, it goes deeper into the air tube and has two 4-40 breech screws, similar to Prod.
I will need one extra hole in the bottom for the trigger assy screw. On a G2, I'll have to drill additional holes to move it forward about 1/4".
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The more I look at that short barreled version the more I like it.
The drawing was completely adequate, and Mike was a pleasure to deal with. My schedule makes shop "play" time sporadic, and he was a patient fellow which is always appreciated.
Feel free to shoot a pm when ever you're ready and we can look at the Gen 2.
Regards,
Al
Will do. I'll provide info on the "standard" G2 end cap, and what is also needed. In general, it goes deeper into the air tube and has two 4-40 breech screws, similar to Prod.
I will need one extra hole in the bottom for the trigger assy screw. On a G2, I'll have to drill additional holes to move it forward about 1/4".
That would be awesome to have the extra hole for the Prod trigger group built into the design.....
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I had looked at the oem end cap, which does extend far enough, wouldn't be too hard to drill and tap for the trigger screw. Now me doing that in SS, much lower chance of success. :)
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I had looked at the oem end cap, which does extend far enough, wouldn't be too hard to drill and tap for the trigger screw. Now me doing that in SS, much lower chance of success. :)
BTW, the adapter is made of 4130, not SS....
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The polishing fooled me. :)
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Great build Mike! I have a Gen1 .22 Mrod I picked up a few months ago I haven't even shot. I've toyed with the idea of making it into a short carbine in the 35" range but would need a short tube also. Gives me things to ponder on. Again though very cool build!
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Agreed. It is weird that I was able to order one at the same time you did, my order was fulfilled but yours wasn't....Perhaps they will become a little more organized in 2021???
I'm glad you caught that- You ordered yours AFTER I did, and actually got them- I never even got an email back... ;D >:(
I can't stop looking at the short version with the AR adapter... I keep thinking about getting a folding adapter and an adjustable stock like this:
(https://mdttac.com/media/catalog/product/cache/772eaea42ae5aaab2a128de135ea6bd1/s/c/scs-family-complete-black_1.jpg)
Combine it w/a AR grip adapter and a precision rifle grip? Oh man. Nice compact little hammer!!
I like the looks of those. On Prods, with straight adapters, had the opposite problem, too little comb, and had to use high or extra high rings. This, having a higher breech. might be ok as is.
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Great build Mike! I have a Gen1 .22 Mrod I picked up a few months ago I haven't even shot. I've toyed with the idea of making it into a short carbine in the 35" range but would need a short tube also. Gives me things to ponder on. Again though very cool build!
Thanks Dillon. I was a bit late to the Mrod party, but that is typically how I roll with most of my hobbies, I'm not much of an early adopter. A short .22 sounds interesting.
John, those stocks look cool. However I am considering going in the opposite direction towards a minimalistic fixed buffer tube style stock.
In the junk bin I had a leftover Mossberg 500 forearm. After heating it up it will tightly snap on the tube. Notched it for the gauge, I think I like it.
BTW, Dillon this is what 35" looks like. 12.5" barrel with a Ronin hanging off, stock fully extended.
(https://i.imgur.com/pOPxtMk.jpg)
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Mike,
I have used those shotgun forearms on a couple of projects and like them. I was thinking that it would look good on these carbines. Thx for proving it. :)
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John, those stocks look cool. However I am considering going in the opposite direction towards a minimalistic fixed buffer tube style stock.
In the junk bin I had a leftover Mossberg 500 forearm. After heating it up it will tightly snap on the tube. Notched it for the gauge, I think I like it.
(https://i.imgur.com/pOPxtMk.jpg)
Mike, very nice idea, it looks like it belong there.
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I used a 500 forearm when I built my PP700. ;)
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I used a 500 forearm when I built my PP700. ;)
That looks good. they make for a nice snap fit in some applications. No need for additional screws, hardware, etc.
Bob, John---Thanks... just one more reason to hang onto all of that "junk." I picked up that particular piece some time back to use on one of my 500's, but didn't care for the way it fit. While looking for a sling swivel I stumbled across it and the lightbulb went off.
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I used them on double tube Prods, but they needed a "filler" pipe for the small tube. Also, mounting screws to prevent rotation, etc. I have one on the shelf, that has been sanded on to fit the larger Mrod tube. I never thought of expanding it to fit or sliding over receiever, like you did.
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(http://joefish.homestead.com/M4Rod1.jpg)
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(http://joefish.homestead.com/M4Rod1.jpg)
I remember seeing that one, looks great.
I heated the forearm and a spare tube to somewhere around 170-180 degrees, then used a vice to press it onto the tube. I kept it hot for a half hour or so then let it cool down. Now you can slide it off and on by tapping it with a soft faced hammer/mallet. This particular forearm was solid nylon, not impregnated with fiberglass etc, so heating it worked well.
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A pic of the largest configuration. 16" barrel. Setup this way with the simplified balanced valve it does 10 shots in the 825-875-825fps range. A bit loud with the Ronin though, adding the 6" extension or putting on the Emperor quiets it down significantly. When the short tube arrives this configuration will allow for fitting of a 350cc bottle vs the 220cc pictured.
(https://i.imgur.com/owwkC32.jpg)
I really like the feel of the gun in this configuration. it carries and shoulders well. Cheek weld is perfect, the shotgun forearm is nice and "grippy". When I build my next Brod, it will be very similar to this, but it will be built on a Gen 2 tube/breech.
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Very nice! 8)
I could see my gen 2 parts coming together very close to that. ;)
If I could ask, where is the balance/fulcrum point?
The larger bottle should give at least 50% more shots, even though a small loss of tube cc's.
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Very nice! 8)
I could see my gen 2 parts coming together very close to that. ;)
If I could ask, where is the balance/fulcrum point?
The larger bottle should give at least 50% more shots, even though a small loss of tube cc's.
It balances right at the gauge.
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Perfect!
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A really nice build; you have one heck of a gun there. :D
Jesse
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A really nice build; you have one heck of a gun there. :D
Jesse
Thank you Jesse. It has been fun playing with the modularity of the Gen 1 Mrod platform.
I put together another configuration today. Swapped barrel over to an 18" GM .25 barrel with the choke removed and bolt to a .22 Gen 1 bolt that is sleeved up to .25. Thanks to sealing the valve to breech and the Gen 1 bolt design this is easily accomplished without removing the breech. Literally a 5 minute process to go from .357 to .25. Overall length is 39" with a Tatsu and the stock fully extended.
(https://i.imgur.com/xBmfIx5.jpg)
I didn't touch the SSG and ran a couple shots of JSB MkII's across the chronograph---they were running a little hot at 1060fps!!!!! 50gr slugs went in the 850's. Dialed it down to a MkII tune that starts at 875 and peeks at 910 then back down to the 870's. It seems to do around 25 or so shots tuned like this.
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I got the 25/30 mag from Darko. After opening it up, it will be very thin to the outside diameter, for 357.
I measured 0.040" to the edge on a 0.310" hole. Assuming 0.367" hole, only leaves 0.010". Probably need to go to a larger diameter. Probably too much rework for the sales potential. :(
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I got the 25/30 mag from Darko. After opening it up, it will be very thin to the outside diameter, for 357.
I measured 0.040" to the edge on a 0.310" hole. Assuming 0.367" hole, only leaves 0.010". Probably need to go to a larger diameter. Probably too much rework for the sales potential. :(
Thanks for taking a look inside.... It sounds like an OEM style mag is the only option for .357. We just have to find someone willing and capable of helping.
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Methinks for .357, we'll be stuck with single loading.
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Methinks for .357, we'll be stuck with single loading.
Hope not. Looking at an oem 25 mag, it looks to have the same issue.
Maybe the barrel slot can be longer, and you would push it further on. That can get the holes further away from the edge, but might be into the spring cavity.
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Methinks for .357, we'll be stuck with single loading.
Hope not. Looking at an oem 25 mag, it looks to have the same issue.
Maybe the barrel slot can be longer, and you would push it further on. That can get the holes further away from the edge, but might be into the spring cavity.
Bob made a 5 shot .357 pellet mag out of an OEM .25 mag, IIRC.
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Even at 5 shots, a mag would be the cherry on top!!
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A really nice build; you have one heck of a gun there. :D
Jesse
Thank you Jesse. It has been fun playing with the modularity of the Gen 1 Mrod platform.
I put together another configuration today. Swapped barrel over to an 18" GM .25 barrel with the choke removed and bolt to a .22 Gen 1 bolt that is sleeved up to .25. Thanks to sealing the valve to breech and the Gen 1 bolt design this is easily accomplished without removing the breech. Literally a 5 minute process to go from .357 to .25. Overall length is 39" with a Tatsu and the stock fully extended.
(https://i.imgur.com/xBmfIx5.jpg)
I didn't touch the SSG and ran a couple shots of JSB MkII's across the chronograph---they were running a little hot at 1060fps!!!!! 50gr slugs went in the 850's. Dialed it down to a MkII tune that starts at 875 and peeks at 910 then back down to the 870's. It seems to do around 25 or so shots tuned like this.
After quite a bit of frustration around accuracy of the .25 barrel I realized I was trying to run too hot for the GM's relatively fast twist. MkII's running in the 950-990fps range were producing 4-6" groups at 80 yards. I dialed velocity back down to a 870-900-870fps string and found decent accuracy.
here is a 25 shot string from 2700psi down to 1700psi. 5 shots on each bull, with the center bull being my last target. Distance is 80 yards, MKII's tuned at 870-900-870fps. Conditions weren't the best with a swirling wind and drizzling rain, but I think this is representative of its performance.
This little modular monster goes from a 120fpe .357 to a 58fpe .25 with a 5 minute bolt/barrel change and a slight SSG adjustment.
(https://i.imgur.com/0QxPIKP.jpg)
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VERY nice!! If only caliber swaps were this easy w/a BD!! ;D
Although, w/a FLEX-type bolt probe, I guess it could be!
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A long awaited package from RI arrived today. The package contained some very cool parts, perfectly machined and packaged. Amongst the assortment of coolness was this little 7" Gen 1 Brod tube. I had other things I needed to do but I couldn't resist putting the short Brod tube in.
(https://i.imgur.com/Gb51NGE.jpg)
The short tube allows for a 350cc bottle with the 16" barrel. I don't recall how long a 500cc is, but it may fit as well??
Setup like this with the Ronin and extension, 120fpe is truly backyard friendly. Shot count is somewhere in the mid to high 30's. Haven't shot it enough yet.
I believe I have enough parts to reassemble the 8.5" barreled pistol, I just need to pick up another Prod trigger assembly. If anyone has a spare to sell shoot me a PM.
(https://i.imgur.com/hUiw9rr.jpg)
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Even cooler than before! 8) 8) 8)
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I swapped tanks between this and a Gauntlet .25. This gun being unregulated couldn't take advantage of a 4500psi tank so it made sense to move the old 480cc Talon Tunes tank over to this gun and the 350cc 4500psi tank to the regulated Gauntlet.
(https://i.imgur.com/Q4CmncI.jpg)
It is amazing how much louder the gun is without the DonnyFL extension on the Ronin...
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Something still wasn't quite right with how the gun felt. So, let's try this for a bit..
(https://i.imgur.com/Wb2dcfq.jpg)
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That ultra short tube looks fantastic!
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Another configuration.... This time with an Mrod tube extension screwed in place of the bottle block and using the 12 inch barrel.
(https://i.imgur.com/9w8n8Sw.jpg)
This little tube is probably around ~80cc? It yields 10 shots of 91gr NOE pellets 625-670-625fps.
Ultimately I think I prefer the 12" barrel configurations. I have a 23ci bottle on order for when I want to put the tank on it. The pic with a skinny tank and 12" barrel is a 17ci tank..
The short 7" tube with no gauge block design allows for fairly straight forward conversion of the valve between Simplified Balanced valve and Powerhouse configurations by unscrewing the balance piston carrier and changing out poppets. In Powerhouse format and with the 16" barrel it will push a 174gr BBT 750fps, 134gr BBT 805fps, and 91gr pellets 890fps.
(https://i.imgur.com/QdT0yrw.jpg)
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VERY cool!!
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VERY cool!!
Thanks! This has grown to be my favorite Lego kit.
The modified Koi worked surprisingly well, but was still a fairly sharp "POW". So I modified another shroud I had but it is too fat for the longer tanks. Right now it is setup with a 13ci tank.
(https://i.imgur.com/Pu09F9s.jpg)
(https://i.imgur.com/VCgjcBC.jpg)
Collapsed it is 25.5" long, extended with the can it is 36" long
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Mini-Mike Mock-up:
Mike, Tom, and I collaborated on getting an AR stock adapter made for G2 Mrod tube, but using the Prod trigger assy w/Lloyd's sear. We collaborated on the dimensions, and Al did the hard work of making it into reality. Beautiful work at that. It does require drilling a couple of holes in the tube and threading one.
Originally, I was last on the list to receive one. Tom went another path after not being able to find a sear. Mike is still having fun with the G1 and other projects, but will probably get back to it, in the future.
So, being the first, had to at least get the mock-up done to verify, which I did. The AR adapter was perfect, and the only issue was my ability to get perfect hole placement. More accurately, my inability. ::)
Now, its a Mini-Mike because it is only 22 cal, vs Mike's favorite, 357. ;)
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Mini-Mike Mock-up:
Mike, Tom, and I collaborated on getting an AR stock adapter made for G2 Mrod tube, but using the Prod trigger assy w/Lloyd's sear. We collaborated on the dimensions, and Al did the hard work of making it into reality. Beautiful work at that. It does require drilling a couple of holes in the tube and threading one.
Originally, I was last on the list to receive one. Tom went another path after not being able to find a sear. Mike is still having fun with the G1 and other projects, but will probably get back to it, in the future.
So, being the first, had to at least get the mock-up done to verify, which I did. The AR adapter was perfect, and the only issue was my ability to get perfect hole placement. More accurately, my inability. ::)
Now, its a Mini-Mike because it is only 22 cal, vs Mike's favorite, 357. ;)
I'm ecstatic that the AR adapter's holes and such are spot on! That adapter looks fantastic!!
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Mini-Mike Mock-up:
Mike, Tom, and I collaborated on getting an AR stock adapter made for G2 Mrod tube, but using the Prod trigger assy w/Lloyd's sear. We collaborated on the dimensions, and Al did the hard work of making it into reality. Beautiful work at that. It does require drilling a couple of holes in the tube and threading one.
Originally, I was last on the list to receive one. Tom went another path after not being able to find a sear. Mike is still having fun with the G1 and other projects, but will probably get back to it, in the future.
So, being the first, had to at least get the mock-up done to verify, which I did. The AR adapter was perfect, and the only issue was my ability to get perfect hole placement. More accurately, my inability. ::)
Now, its a Mini-Mike because it is only 22 cal, vs Mike's favorite, 357. ;)
I'm ecstatic that the AR adapter's holes and such are spot on! That adapter looks fantastic!!
Looking good.
The adapter worked out perfectly. I only hope others will buy a few more from Al.
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Dustiing off this old thread as I dusted off this kit of legos today.
Current configuration is regulated at 2000psi with 17ci tank. Does 24 shots of 80gr NOE pellets at 775fps on a 3kpsi fill. It really smacks my reactive targets.
(https://i.imgur.com/BrdRQkX.jpg)
Hopefully in upcoming months some long awaited parts modifications will be complete and I can assemble the remaining configurations.
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VERY cool!! I've also been thinking about re-visiting my version of this build! Though, in .30...
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VERY cool!! I've also been thinking about re-visiting my version of this build! Though, in .30...
Hey Tom-
Long time no talk.... I was wondering if you ever picked your .30 up again. Last I recall you picked up an Impact and a Flex.
This evening I shot some 1 hole groups at 50 yards and tried my luck at 100.....lobbing 81gr JSBs at 750fps.
I didn't have enough adjustment in my scope to get on target. So I started guesstimating holdover. Ultimately with all the up dialed in and using where the crosshair goes from fine to coarse I was able to get somewhat on target.
The bottom left group represents the first attempt at guessing holdover. then the middle group was the second attempt. Then the top group was 5 shots holding the coarse part of the crosshairs on the center bull of the top target.
(https://i.imgur.com/weJWyeo.png)