Long story short since I already had a thread on this, my FS 9mm M&P has early unlocking issues. I have an Apex hard sear and polished/rounded the striker block. It has a better trigger than 80% of my handguns.

Originally it shot 10" groups at 15 yards with 7 different brands of ammo in 3 different weights weather bench resting or off hand, sent it to S&W and all they did was adjust the rear sight, took it to the range and they adjusted it to shoot to far to the right and I still got 10" groups.

While at the first range trip after I got it back I put a 20# recoil spring in it and the groups went down to 4" at 15 yards, went home and my laser bore sighter showed the rear sight was indeed off, I set the sight back where it was suppose to be and am now waiting for Apex to come out for a real fix which includes new locking blocks and/or barrels.

Basically, it's not always the shooter and the M&Ps don't have some special,one of a kind trigger that will take crates of rounds to learn. It may or may not be the gun, but the only way to know is to eliminate every possibility like I did, otherwise people will tell you it's you learning the gun. Not all are effected but mine is and S&W refused to fix it.

That's the short version...really it is.