The power of a full-size pistol in a palm-sized package! It's based on the Lilliput pistol, the second smallest semi-auto ever made. Music: musicisvfr.com/... Japanese only - you may want to use Google Translate!
Nice work! :-) To simplify the mechanism try experimenting with the shapes of the Tenku-kaku mechanisms and the other blowback types. I used those as inspiration for my transparent 1911. I think you could get down to three moving parts for this nice little compact.
Does the doubled-over rubber bands make the launch speed weaker compared to a single one? Cause when the rubber band flies, wouldn't it untwist itself while flying, making it vibrate losing energy? Either way, nice design! I like how compact it is yet features solid performance.