I recently purchased a fourth generation Glock 19. I've put about 400 rounds through it in the last week. In the first two magazines I had three FTFs. It functioned very well for a while after that. Then, somewhere in the 200s, it jammed. Again, somewhere in the 300s it jammed. That's five jams in the first 400 rounds. I'm fairly inexperienced shooting handguns, so it's possible that I'm limpwristing, but two of the jams were when other guys were shooting it. I've been using cheap ammo (Federal FMJ, Magtech Lawman FMJ, and Remington UMC). I bought this with the intention of doing a lot of training with it and using it as a carry piece. I've always heard about Glocks with thousands of rounds and not one malfunction. Also, I'm shooting very poorly. I bought a lot of ammo the weekend I bought my gun. I wanted to go out and shoot it a lot to build confidence in it as a carry piece, but I've done the opposite. I'm all over the place with it. I'm always high and left, with a poor shot group. After shooting a couple hundred rounds yesterday and becoming very frustrated, I picked up an XD9SC and shot a nice tight, on-target group. I put fifteen rounds in a smaller group than five rounds with the Glock. I've shot a box of my personal defense rounds through it, and didn't have any problems, but between the gun jamming with the other ammo, and me just shooting poorly, I'm considering not carrying at all. I really want to like this gun. I really want to trust this gun. So far though, that hasn't happened. Y'all have any ideas?