[dpvu]

Alright, I have a KSC USP with a metal slide and enhanced recoil spring. The slide locks back when I rack the slide but usually not after firing the last shot. I thought the seal between the mag and chamber wasn't good so I shimmed the rubber on one of the mags but it doesn't appear to be improving things.

Any ideas? The gun appears to be firing well, I just want the slide to lock back now.