Originally Posted by rmruder
Thanks for all the input guys!
Based on all this, I will definitely go to my local range and do some drills with a fully loaded mag to see if I can find out if it was just me. I was only concerned about it possibly being something with my pistol after reading about some other folks having this problem and S&W providing a newer mag catch to solve it. I then saw where my pistol was in the series range with the problems and.......Other than that I figured it was probably me to start with......
Maybe too much reading and over-thinking this....It looks like operator error rather than equipment problems.
I own a M&P .40 as well and one thing I have noticed is that when the mag if loaded to full cap. it take a little more 'umph' to seat it. I think it also has a hard time even when there isn't one in the chamber... Either carry clips with 14 or use a little more force when you reload. 14 rounds is more than enough to get the job done IMHO.
It may have something to do with the guiding mechanic used to hold the round into place on the slide and the stiffness of the spring in the mag. I've noticed that I am unable to place a round into the chamber through the ejection port because of a notch/hook on the slide that will only allow the round to come from the mag well.
Post if S&W fixes the problem though!