Originally Posted By jerp225:
I have the M&P 15X and the only complaint I have is that it is picky about ammo. It does not like steel cased ammo, and most people will tell you that you should NEVER use steel cased ammo in your AR. My thought is if it can't shoot the steel then it is a quality issue with the rifle. Now if I have it dripping wet with lube it will shoot the steel stuff. I just built a PSA and it will eat anything and cost me about $300 less. Quality is top notch in the M&P though, mine came with a Troy rear folding sight and quad rail. I have since added a Eotech and it is my go to SHTF rifle.
I had the same experience with my M&P 15 a few years back. Ate brass cased all day long, but any steel cased would frequently stick in the chamber. Sent it back to S&W who apparently reamed the chamber out, and the problems persisted.
My 20" PSA build eats anything. I would get a PSA over an M&P15