i did the meteor style experiment too.. I still have the head somewhere... it was liek an inverted top hat, with a sliding piston head holding the seal, and a rubber buffer behind it. Unfortunately it had the problem that it expanded during the firing cycle, robbing power, not just at the point of bounce. but maybe I was just impatient and should have tried more fine tuning.
I think the floating inertia design has more promise... maybe add strength by boring a 10mm hole clear through the weight and letting the piston rod pass all the way thru to the "real" nose ?
Always looking for any cheap, interesting, knackered "project" guns. Thanks, JB.