Re: Twist Rates and Velocity?
Montana said that with the same muzzle velocity, regardless of barrel length ,the spin would be the same. I totally agree with that. With a 1 in 9 twist, the bullet rotates once each 9 inches of travel . If a 1/9 travels 81 inches in one minute , it would have revolved 9 times thus would have 9rpm. Same bullet travels same distance in 30 seconds, now is rotating at 18 rpm. When it travels at 3000 feet/ second ,it rotates at 240,000 rpm. The faster it goes, the faster it spins, but still rotates only once for each 9 inches traveled. If you go to a 1 in14 twist, the 3000 fps bullet only rotates at 154,286 rpm. That is why some light varmet bullets don't do well in high speed fast twist situations. 300 thousand rpms tends to be hard on the pistons!
Phil Conklin.... Shooting Instructor for The Best of the West