 That's why you can sit there and hit a huge bucket of gelatin, and the bullet just goes straight through it. But if you shoot even thin aluminum, especially with 5.56, it's so unstable. By the time it hits the other aluminum on the other side of the can, it's a much larger hole. And if you shoot something a little bit thicker, it fragments, and it basically has five or six holes on the other side like a shotgun.