i connected a plastic tube about 7 or 8 inchs long onto a butane can im wondering if when i push down on the can and put a match near it can the fire go back into the can and make the can explode
Sure can, even if you've posted this in the wrong category. Funny thing about fire... it likes to burn as long as possible so if the flame makes it's way into the tube... you should duck. Don't be foolish, keep your hands, fingers, eyebrows, etc and quit playing with fire.