trebuchet bump!
My older brother made a breech-loader of rear-threaded galvinized plumbing pipe with a cap drilled for a fuse
Homemade 10X pine pistol handle with 2 steel barrel straps
Small Chinese firecrackers, paper-wrapped marbles
Match
Mudbank
Sucker would go pretty deep in the mud
Do not try this at home kiddies
When I was a kid, I made a small pistol out of a piece of fiberglass tubing with a cap on the back just behind a hole in the top into which I'd firmly slide a single firecracker (which happened to be the perfect length and didn't stick out). I would stand at one end of the garage and shoot two-liter pop bottle caps half-filled with wax through pizza boxes on the other. It was fun and sounded really cool.