“The full-auto sear from the airsoft gun in question is a sort of paddle-like device which operates much like the real counterpart.”
Huh? Look here for info (wiki on this is decent): http://en.wikipedia.org/wiki/Airsoft_gun#Automatic_electric_guns There isn’t even a sear present. Or by sear do you mean the fire control group? In the airsoft, the fire control group is basically an electric switch for the air pump, isn’t it? That’s NOTHING like the fire control group of an AR, AK, or any other real firearm.
Oooh, there’s also the little plastic gear (toothed about 1/2 the way around) that spins to pull the cylinder back and then let it fly forward under spring power. In other words, the gear that drives the air pump. None of that would survice the pressure from a single .22 round, let alone a 9mm or .223...
Here is a video which does a better job of showing the internals of a GBB, though its for an Inokatsu and not WE brand. look around the 55sec-1min mark: http://www.youtube.com/watch?v=tbJZJeTIMQ8
The actual WE gas blowback internal view from www.gasguns.info:
The thing with the little roller is the "hammer". It actually strikes a valve stem beneath the screw plate. The sheet metal thing to the left of the hammer, with a coil spring in it, is the gas blowback equivalent of an autosear.