Saw this and just thought I would pass it along...real good info!The math to figure RPM of a bullet for a given velocity in a given twist barrel is real simple. It is:
RPM = (Velocity * 60 * 12)/Twist (in inches)
Using that formula, you can plug in some real world numbers and quickly see what I mean about it taking a lot of velocity to make up for a little bit of twist. For example, a bullet with a muzzle velocity of 3500 fps leaves a 12 twist barrel at 210,000 rpm. Using a 14 twist barrel, you have to increas the velocity all the way to 4080 fps, an increase of nearly 600 fps, to get the same spin as the 12 twist at 3500 fps.
Moral of the story... With notable exceptions, for the most part, you can't get there from here, trying to make up for a slower twist by means of increased velocity.