I've seen people suggest that blocking the slide is a handicap, because it stops the pistol from cycling - but having seen what happens when you jam a pistol into a pigs carcass and pull the trigger, I'd say that isn't much of a concern. Even without blocking the slide, you're looking at an ungodly mess and a pistol that, if you're lucky, might get a second shot off. Two things are amazing about contact shooting with a handgun, first the level of damage is off the scale - you have 3 wound mechanisms working at full force - penetration, blast and burning, and second, it's amazing how much crap ends up inside the gun's mechanism.