Gunblade diagrams

So how does a gunblade work, anyway? I was playing FF8 one time, and this question kept bugging me. So I did this thing you're looking at here. The basic idea is, you pull the trigger right as you're smacking somebody with it, and the gun fires a blank cartridge to either make the gun recoil downward or actuate a pneumatic piston, increasing the force with which the blade strikes its target. Not really a practical weapon, but... whatever. That second one from the top would make a pretty cool blacksmithing project, actually.

Believe it or not, this is actually not the nerdiest thing I've ever done.