Oh, I never meant to imply that it was safe, its not safe at all. All you can do in minimize exposure. When we did it, we were shooing down into an empty quarry using WW2 era 30-06 black tip M2 AP from a scoped hunting rifle. Would I do it again? Maybe....
It's impossible to predict in what direction and how far they will travel. I'm normally down for questionable shooting activities but shooting propane tanks is not a safe activity
That's why you chain it down. For the record I protested it and took shelter behind a building on the farm. Was THE coolest ---- I've EVER SEEN.
.223 into a can of Great Stuff spray foam is really lame. 7.62x54r into a can of Great Stuff spray foam is GREAT STUFF! Also shot a full can of orange marker paint cause the nozzle broke off and I'd pay $100 to have a video of what we did. After one shot it went flying off in one direction, then I started unloading the magazine into it. Eventually the can ended up 25 feet in the air where my buddy blasted it with a 12 gauge. A 28 and 50 year old in tears from laughter was the end result.
I'll take some pictures sometime but I built a little steel frame that you can put swinging targets on for either pistol or centerfire rifles. Shooting paper is kinda boring but when you hear a "ting!" at 300 meters it's somewhat satisfying.
At a friends ranch where we used to shoot, we placed the remnants of a smallish steel propane tank that had ruptured in a house fire out right around 400 yards. It made this awesome "BOOOOOONNNGGG!" when you hit it with anything centerfire.
We also used to take beer bottles filled with gasoline and shoot them with 5.56 milsurp tracers or just left lit roadflares nearby. Good times
I am fortunate to have a three bermed pistol bay at home, along with a 300 yard rifle range. I made this last year. Plate racks are fun to shoot. Yes, it has two Miata spares on one end to trailer it around.
We went to the range today and shot flippy targets (ones that reset when you hit the center target) as well as paper targets on a custom paper target holder I built (kind of like a really tough campaign sign). One of the guys brought two dozen eggs. I've never shot them before but it was kind of fun.