Quote Originally Posted by Shed tuner View Post
I do wonder what's to stop the trigger being pulled and the piston hitting the half open front end of the gun, or a finger. Maybe the clearance could be tweaked so the cylinder wall itself was virtually touching the piston face as it swung up, thereby blocking it's escape route (and no chance of getting a finger in the gap).

The real design problem though is no mechanical advantage on cocking.
They are still quite nice to use. Very well made but not brilliantly accurate. piston washers are a sod to make and springs hard to source. Mine runs with a piece of spring I got off you. Haven't got a clue what it was out of originally but once reworked it functions. Not much use over about 6 yards though due to the low power and rudimentary sights