The Idaho potato gun consists of the following. Eating a large can of chili con carne' then applying KY warming effects to your anus, and sticking a potato in your ass. The goal is to fart the potato farther than five feet. If this is not accomplished, then the "shooter" has to eat it. If it is accomplished, then the person who challenged the other person has to eat it.
Mike challenged Konrad to a Idaho potato gun contest to see who was going to by the beer for the nite. Konrad ate the chili and stuffed the potato up his ass and shot it seven feet. Mike had to eat the potato. Dude you suck, you shot it farther than five feet! You bastard !