well my mom came home one day when I was prob 13, with an article explaining how some guy had taken an empty CO2 cartridge, and proceeded to fill it with strike anywhere matches, in the process it blew up in his hands, and thus loosing one or two fingers. After hearing this, I told my mom I would never be stupid enough to do that, that is blow off my fingers, I then proceeded to think that cutting off the match heads was not good enough, so I scraped off the ends of a box of match heads, filled a CO2 cartridge, packed it down and taped over the end. went outside, and threw it in the air. nothing, so I got my sling shot, and shot it at a large rock in the ground, it proceeded to go right by my( to this day I do not know how it did not hit me.) but it did fly over 100 yards, and hit the brand new garage door which my dad had put in the weekend before. as soon as he got home he saw the dent, and asked me. I said I dont know, and still to this day he does not know.