Same here. The bolt is still closing when I use a little force but the Promag is still catching on the bottom of the carrier as it cycles. I don't trust it enough to fire. Not worth the hassle to return it, either. If someone wants it for $30 shipped (20rd mag; paid $40 for it), it's all yours. I'll just use the cash towards US-made UMP floor plates and followers for my UMP mags like I should have done in the first place.I am also not impressed with their quality. Mine will not go in the gun with the bolt closed. It seems to feed fine, but it is definitely not German engineering.