Having an AR issue, any help would be appreciated

[rdavidson]

5.5 oz buffer seems pretty heavy for 14.5 regardless of gas system.
If running a mid length 14.5 try carbine buffer first then h buffer.
If it's a carbine system run h first then h2.

By the sounds of things you carbine system.
I would try h2 first.

 

[Amazingkg3]

Had identical issues with a Daniel defense I built. It was a carbine length 14.5, but I put a big three chamber brake on it. It would constantly stove pipe the casing in the chamber, and did all of the solutions you have used. Only thing that corrected it was getting a heavier buffer, and losing the brake for an A2. Ran great after that. Definitely overgassing going on.

UPDATE:

I swapped out the gas rings and installed an enhanced extractor, no solution... then I swapped out the buffer spring, on the assumption that the old one was worn out, and replaced it with a new carbine length spring. That made the problem worse somehow - it failed every shot with Pmags and every few shots with LAR-15 mags. So...maybe a carbine length spring wasn't the right one, but it's a 14.5" upper sitting on a Bushy XM-15-E2S lower, so I think it does need the shorter spring. The issue is the same as before - the spent brass is extracted but rotates up to 180 degrees in the breech and doesn't get ejected, then it strips another round and everything gets jammed up.

So now, by little more than the process of elimination, I'm going on the assumption that it's overgassing and everything is just happening too quickly in the breech, so I'm thinking of replacing what I believe is a standard weight buffer with an extra-heavy one, around 5.5oz. It's the last thing I can think of. I have a hunch that the solution is probably pretty simple...and it's out there somewhere. Thoughts?

 

[Paul_M]

UPDATE: Problem solved! I think it was a dual problem of overgassing and an extractor issue... A friend watching me shoot noticed that the spent brass was getting held up in the extractor, just a split second longer than it should have been, it was too tight and not releasing it, so I removed the rubber o-ring that came with the extractor, and I replaced the buffer with a Spike's Tactical T2 (H2) heavy buffer. It hasn't failed since. Thanks for your help, Nutz.