Ballistic gel "farts" after a bullet passes through it

Ballistic fart

This Imgur video shows a bullet of unknown caliber passing through a block of ballistic gelatin, "a testing medium scientifically correlated to swine muscle tissue") followed by a mysterious explosion within the gelatin (one Imgur commenter says it's just "the fire tetrahedron of, oxygen, fuel & heat" trapped in the gel) which produces the most satisfying little fart when it's done. (via JWZ)