My wife and I went out shooting this afternoon and we shot my GP100 and my XDm 3.8" .40 S&W. My wife is pretty new to shooting, especially pistol shooting. She was shooting my XDm and had the slide not lock back on the last shot a couple of times. There was never a FTF or FTE, just failure to lock back on the last shot. I thought that it might be due to limp wristing, but I'm not that experienced with semi-auto pistol shooting either. I have never had the slide not lock back for me so I was thinking it was shooter related rather than mechanical.