mixflip So that video proves what? I say it shows a dirty weapon/ lack of lube compounded by bad mags! I wonder if they were those plastic Pmags!!! Yep those were Pmags and he kept stuffing the same F'd up mag back in!! I've seen a torture test of the M4 DI I still haven't seen how many rounds it takes to kill a piston gun- don't happen to have that video do you? I'll bet the forearm bursts into flame well before the 500 round mark! Just like a AK will!