I just recently built a 9mm upper using CMMGs radial delayed bolt and barrel, using CMMG branded MEAN Endomags. I have not shot it extensively yet. Put 30 rounds through it on my M16 lower and 30 rounds on a pistol lower, using same mag. Out of the 60 rounds of factory ammo, I had three misfeeds, where the round did not enter chamber square and ended up getting smashed by bolt. Two were on M16 with MGI buffer, one was with pistol lower and standard carbine buffer. Anybody else see these issues ? I know Amphibian has extensive experience with these setups, but don't recall reading about this problem . Really hoping I can get this resolved.