I had an issue with mine as well. The back plate on rear of slide would slip down enough when fired that it would not return to battery; the bottom of the back plate would catch the frame as is slid forward. Sent it back to S&W last spring, came back and worked fine. Last week I took it out to shoot a couple mags after not firing it for a while, first shot same thing happened. Pushed it back into place, fired a few more rounds with no other issues. Kinda makes you think, if you needed it for something serious and it screwed up like that it might be the difference in winning or losing.
