Just post a Seadoo for sale on Craigslist. People will start sending you machine gun pics as a trade offers.
I like ONE AT A TIME shooting. "Plinking" mostly with a 22. I have a 7mm Remmington Magnum I bought in 1977'. I made a target to shoot across this pond about 125 yards. It was about 5/8" - 3/4" thick about 4 inches in diameter with rings machined into it. I welded a 1/4" by 1" flat bar to a short piece of pipe so it would swing when hit thus dissipating the energy to decrease damage to the target. It was pretty sturdy and I stuck a rod through the top VIOLA. Just what I wanted. The target didn't last long at all. Each hit with the 7mm drilled a 3/8" deep by 3/8" wide hole in the target. My nephew's 243 did about the exact same damage. On that first hit there was a bulge on the back side of the target. I'm talking 5/8" thick metal, So we aimed for the holes in the target. That next shot went clean through the target and tore metal out the back . My cool target was junk pretty quick. It was a shocking revelation for me. Yikes !!