Shamelessly pulled this from another forum. It is part of a larger post about muzzle brakes--but this clip is not out of context. Comments? Personally I am just a wee bit skeptical. "The actual physics that cause the barrel to rise is the the spin on the bullet (i.e. the twist rate) - change the rifling to the other direction and the barrel would go down not up. I think that the concept of rifling a barrel must have been invented in the northern hemisphere by right handed people."