[USP45]

But I began to notice things about the USP. Like after a reload, the slide barely has to be moved to release the slide lock and chamber a round. .

the USP was initially designed so when you did a mag change slamming a new mag in would release the slide.I can duplicate this on my USP 45 and prefer this,although reading at HKPRO boards it was re-designed to be "less likely" to do this.