Rifle: Early Geissele URGI near clone with 14.5 DD barrel. The rifle was using carbine buffer. I was using IMI 77 gr razor core ammo. Surefire SOCOM Gen 2 suppressor.
Without suppressor - normal function.
With suppressor: brass ejected at ~ 2 o’clock, failure to lock on empty magazine (happened twice). This seems strange as a suppressor should help with gas pressure. What could be causing this issue? I experienced no issues with this rifle and different ammo.
I also realized that I was using OK 20 round magazine. I didn’t have a chance to try it with 30 rounders. Could this magazine also have an effect ?
Something similar happened to someone about a week ago. I don’t think you’re short stroking. I think the BCG is out running the bolt catch. Carbine buffer is too light. Try an H2.
I had this happen and yes your bolt is outrunning. A different mag, ie 3rd gen Pmag have much stronger springs and work best. OK and Colt 20 rounders have weakest springs even though I run them a lot.
I also changed to an A5 buffer and it fixed it with Colt 20 rounders although new Pmags worked just fine. I was running a KAC 16 inch SR15, so not a shitty gun. Not the best mags are the real issue is my guess.
PB