This has actually happened to me one time with my .40 When I 'moderately' slammed a mag in, it automatically chambered the first round. I tried to repeat this again with the next mag and haven't been able to yet. I know with some glocks and HK's this is expected behavior, and with the glocks, it seems like the best way to chamber a round as the slide release is so hard to push. (can any glock owners verify this?) I don't see it as much of a problem.