Retro Commando pistol (UPDATE)

[Stevo]

Standard carbine weight, then.

What brand ammo? Were the FTEs stove-piping or still on the bolt face? Or something different?

Gas tube and FSB still pinned and in correct position? Rifle well lubed?

[Bill Hollinger]

Factory Remington 55 gr and Black Hills 62 gr. Yeah, all of the above and they double feed. I did some research and it seems all the 11.5 SBRs and pistols are using the H (3.8 oz) or H2 (4.6 oz) buffers.

[Stevo]

Factory Remington 55 gr and Black Hills 62 gr. Yeah, all of the above and they double feed. I did some research and it seems all the 11.5 SBRs and pistols are using the H (3.8 oz) or H2 (4.6 oz) buffers.

Not all.

My 10.5 and 12.5 run standard weight buffers. In fact, both are underweight by a couple of tenths of oz. Never had an issue with either, except when the gas rings were worn out.

The heavier buffer will help if your bolt is bouncing from moving too quickly from being over-gassed, otherwise it should just make recoil feel a bit softer. Was it operating "violently" when you experienced the FTEs?

[Bill Hollinger]

No, it was running quite smooth and what I felt as mild.

[Stevo]

No, it was running quite smooth and what I felt as mild.

That makes it sound under-gassed. It can't hurt to try a heavier buffer if you have one, but I'm kinda stumped so far.

IMO, when they don't run, ARs can be almost as frustrating as M14s having accuracy issues. All the bits are tuned to work when everything else is in spec, when something is off it can be hard to find.

If Stoner had included an adjustable gas regulator in the original design, most of the AR operating issues could be easily addressed.

[WarPig1976]

Bill, bring along the wife's polish AKM that way when the AR acts up at least you can have some reliable fun...

Sorry, had to go for the low hanging fruit!!!....

[browningautorifle]

an adjustable gas regulator

I had a gas tube with an adjustable system from Dlask. it was sure a neat feature. It had been included because the BBL was 11" and had been over gassed. I had no end of misery after changing the configuration until I welded the gas port closed and started again. The Regulator was a simple block with an allen screw...

[Bill Hollinger]

WarPig, you're bad

Thanks guys I will keep you posted on my progress. I'm taking is out and doing some one shot magazine drills with it to confirm the bolt holds open on each one.

[imarangemaster]

Bill, some of the no-name M4 stocks come with really heavy recoil springs. I would try a Colt from Midway or Brownell's. I picked up a NIW M4 GI buffer spring and my carbine works great. Heck, for that matter, try the spring and buffer from you Colt SP1 carbine.

[Bill Hollinger]

Okay, I went out today and fired a number of one shot from the magazine drills and it functioned flawless on five different magazines. One round in the magazine fire and the bolt holds open. After doing this a number of times I put a full Colt magazine, one I had done one shot drills with, and it jammed on the first round. Failure to eject resulting in a double feed. The empty case still on the bolt with the live round trying to feed from underneath. I cleared the jam and fired the remaining 29 rounds without a problem. I fired three more 30 round magazines with the same rounds and had no issues at all (119 rounds). I thought maybe, just maybe it needed to work itself in but that all changed quick. Figuring the jam problem was done I loaded five rounds into each of the five 20 round Colt magazines I had with me to sight the gun in. The first magazine went great. The second jammed the forth round in as did the rest. I got the gun sighted in and at 25 yards it's perfect! During all this I changed the gas rings, extractor, extractor spring and cleaned and inspected the bolt and bolt carrier. Nothing to be seen!

If I get a chance this weekend I will swap out the BCG with a known working gun and give that a shot. Otherwise, I'll wait for the heavier buffers and test them.

Side note: the ejected casing land at about 2:00 O'clock from aiming point and out about 15 feet.