Nice job here.
However, if I may...do some positive criticism
It's ingenious. But it could be more. ==> It seems like it has too many parts to me. And in general, too many parts = too many failure possibilities.
I like the idea of a mechanical/ electrical hybrid. But in my opinion, you could do it more simple.
See, like using springs on guided rods, some sort of bolt catch/release mechanism that doesn't use compressed air.
However, since this is a cool project and you're doing good with it... kuods
Keep up the good work!
And don't worry...the voice will eventually get lower
Harness the power of precision mixtures of pressurized flammable vapor. Safety first! These are advanced potato guns - not for the beginner.