I have a USP .45 fullsize for about 5 years. Put a good 4 to 5 thousand rounds through it with only one stovepipe until the last few times I've shot it. In about three hundred rounds of two different types of ammo, cheap federal and remington, I have had a failure to feed three times. The case ejects, but the next bullet gets jammed up at the top of the chamber. Kind of with the bottom in the mag and the tip up at the top of the chamber inside. It happened twice with the federal ammo in a row when someone else was shooting with it, and then once later with the remington. The gun is meticulously cleaned after each 100 rounds. Is this a magazine problem or an ammo problem? I do not know if it happened all in the same magazine. Even with snap caps it's very hard to replicate the same jam and I am almost thinking that one round is getting hung up on the one under it somehow. Honestly the ammo I was using looks uneven and like ****, but it was only $18 for 50 at wally world.