Author Topic: Tale of THREE BRods - .25, .30 and .357 Completed, Page 12 !  (Read 19129 times)

rsterne

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Re: Tale of THREE BRods - Adding a .357 Version
« Reply #165 on: November 29, 2018, 03:06:53 PM »
I always mix on a flat surface as well.... actually a notepad, and then just throw away the sheet of paper for a cleanup....  8)

Bob
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rsterne

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Re: Tale of THREE BRods - Adding a .357 Version
« Reply #166 on: November 30, 2018, 06:32:24 PM »
Today was consumed with all the little finishing touches on the three BRods…. I had a slow leak in the new .357 cal, which I found was a leaking plug on the bottom of the WAR tank block.... I had glued in that plug with JB Weld, and there was a slow leak spiralling up the threads.... Since I had glued the plug in, I had to heat it with a torch to break loose the epoxy, and once I got it out and cleaned it up, I shortened the plug 1/16" so that it would miss the ASA threads.... I had previously retapped the plug hole, and I went too deep, and the plug was interfering with the ASA threads.... I also removed the male Foster on the tank block and replaced it with a plug, since you fill the bottle through the regulator.... I sealed the plugs with Teflon tape, and that seems to have done the trick.... Once I had that done, I installed the 500 cc 3000 psi bottle, filled it to 3000 psi, and set it aside....

The .30 cal was leak free, so all I had to do was remove the male Foster on the tank block and replace it with a plug.... After a leak and velocity check, I also installed the bottle on that gun, and also filled it to 3000 psi.... Then it was the .25's turn, and I knew it had a serious leak....

It turned out there were actually three leaks, and it took me half a day to repair them.... The first two were easy, a loose plug and a loose gauge.... It was still leaking, so I stripped the gun down completely and replaced the valve O-ring.... but it wasn't that either.... Eventually I tracked it down to a leaking gauge, and once I replaced that it seems to hold air OK now.... I checked the velocity, and it was still what I wanted, so I installed the bottle on that one too, and filled to 3000 psi....

Here is what they look like, now that they are finished.... All three BRods use a modified .25 cal MRod receiver, bored out forward of the front 4-40 screws to accept a 5/8" OD barrel.... They all use a 500 cc, aluminum, 3000 psi bottle for the reservoir, and an SSG to control the hammer.... and have two gauges, one for the bottle pressure and one for the plenum pressure.... The main tubes are from WAR, I believe they were for the FLEX, and yield an 85 cc plenum, including the valve volume.... The tank blocks are also from WAR.... All of them use .25 cal MRod magazines and bolts, modded as necessary....



The top one is the .357 cal.... It uses a Synrod stock, and a Gen 2 trigger.... The barrel is a 1/2" OD, .357 cal, 26" twist TJs, 27" long, glued inside a high-modulas Carbon Fibre sleeve for added rigidity.... It has a steel hammer and a homemade SS valve, and the porting is 9/32" (0.281") or equivalent throughout…. The bolt nose is sleeved up to .357 cal, and the lockup lug is inceased to 10-32 for additional strength.... The mag is a 6-shot one-of that I modified myself....The regulator is mounted on the bottle, and set at 2200 psi.... This results in 2 mags (12 shots) at 146 FPE, using the 81 gr. JSBs at 900 fps....

The one in the middle is the .30 cal.... It uses a modified Bullpup stock that was a gift from Travis, and a Gen1 trigger.... The barrel is a 1/2" OD, .300 cal, 26" twist TJs, 25" long, also glued inside a high-modulas CF tube.... It has an MDS hammer and an ART-SS valve, one of the first production ones with the smaller poppet front end, and the porting is just over 1/4" (0.257") or equivalent throughout.... The bolt nose is sleeved up to .30 cal, and the lockup lug increased to 10-32 for additional strength.... The mag is a 7-shot from AirGunLab…. The regulator is also mounted on the bottle, and set at 2000 psi.... This results in 4 mags (28 shots) at 98 FPE, using the 50 gr. JSBs at 940 fps.... It will shoot the 44.8 gr. JSBs at about 980, and the 59 gr. NOE Hunter Magnums at 880 fps (101 FPE)….

The bottom BRod is the .25 cal.... It uses an airsoft AR stock, on an adapter that I made myself, and a PRod trigger and grips.... The barrel is a 5/8" OD, .250 cal, 17.7" twist LW, 23.8" long, with polygonal rifling.... It has an MDS hammer, and one buffer O-ring between that and the Cothran Powerhouse valve, with 0.257" or equivalent porting throughout, including an oblong barrel port.... The regulator is adjustable, and mounted in the COBRA tank block.... It was a sample from WAR, as I helped them design it, and is set at 1800 psi.... Having an externally adjustable regulator is nice with the Cothran valve, as you have to change the pressure to change the velocity.... This gun delivers 6 mags (48 shots) at 65 FPE, using the 34 gr. JSBs at 930 fps.... It is easy to increase that, or to reduce the pressure to about 1400 psi to use the 25 gr. JSB Kings if desired.... The way it sits, it will launch the Kings at about 1030 fps, which is way too hot....

This has been an interesting project, and I'm happy to say met all the goals I had.... I did some testing with bullets, running unregulated at 3000 psi, and while the performance was remarkable, I think they are much better guns regulated, and shooting pellets.... I hope to be able to do some testing next Spring, after the snow melts.... I must thank Travis for the big box of "spare parts" he sent me when he moved shop a couple of years ago.... Without that, these three BRods would have never materialized....  8)

Bob
« Last Edit: November 30, 2018, 06:48:32 PM by rsterne »
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Alan

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Re: Tale of THREE BRods - Adding a .357 Version
« Reply #167 on: December 01, 2018, 04:04:20 AM »
Wouldn't it be nice, if all you had to do now, was shoot them all every day? Alas, there are other things which must be done.
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Alan

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.

rsterne

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Re: Tale of THREE BRods - .25, .30 and .357 Completed, Page 12!
« Reply #168 on: December 01, 2018, 08:14:41 AM »
Two more years of Motel, and THEN I hope to have some shooting time....  ::)

So much to do, so little time....  ;D

Bob
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bnowlin

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Re: Tale of THREE BRods - .25, .30 and .357 Completed, Page 12!
« Reply #169 on: December 01, 2018, 09:06:11 AM »
Great job Bob on the Brods.  With all those other things going on I haven't been able to shoot for a month.
Bobn