good advice so far. from the sounds of it, it isn't any one magazine, so that eliminates that. you might try not loading the magazines all the way, ie- 28 rds in a 30rder, or 18 in a 20 round, see if that helps. try different ammo, different lube, that's worth a shot. other than that, look on Bravo Company's site, and add an O-ring, black insert, and different spring to your extractor. worth the money and the effort.