When I was in hs, we played with them. We also made napalm, and even a killer potato cannon. Ours was mig wielded, made of stainless steel wiht an 8 foot barrel. We had an 8" screw steel screw in cap on the chamber that could take alot of pressure from the ether.... and an electronic ignition with a car battery. It would lob a potato a good 300 yards, fold over half of a stop sign, and bust out car windshields. I'm surprise we never got arested for the shit we shot.