Who's this Joel character you mention? Sounds like one of those nutcases who likes to blow up things and do crazy stuff.
I really like the adjustable cannon and it's hightech base...a la shopping cart!
For launching beers, I think MB would do fine for testing...mind you I wouldn't drink the stuff. Go BIG like a FOSTERS OIL CAN. Somehow I cannot see the justification of wasting a good beer this way... please note... good beer.
I'll have to sleep on the math tonight to get an accurate psi figure for a HoJo's target from Pink's. I've shot tennis balls, potatoes, eggs, handballs, marbles, ball bearings, softballs, baseballs.... basically almost anything round and smaller than a softball. Beer cans? I like it! Let's do soda 1st... like a diet coke with a Mentos ready to 'drop in' upon launch.
Nice find RR!