He retired years ago from the Army over fifteen years ago and has never owned any AR, maybe used one just a few times. Brand-new 'M4': straight from the gun store box. He knew that at the very low price the quality might need be very good, so he is Not bothered by it. But the constant problems seem so strange. My recent, former S&W AR had a perfect operation. We were shooting about two-three boxes of US-made ammo, and trying to adjust the sights. Suddenly the gun suffered frequent problems where the brass extracted well, but the next round only went part way into the chamber. And at least twice the trigger was fully aft, not resetting. Could it be a stuck spring in the buffer tube? Just a Wild guess.....otherwise this 'thread' would not be here. He really enjoyed my solid Maadi (ARM) and AMD-65 (TGI) AKs after giving up on his brand-new rifle; maybe This will motivate some educated guesses.