Re: revolutions per minute debate
All you are saying is that a 1:8 twist is a 1:8 twist regardless of velocity.
GG was asking what happens (not a vacuum trajectory) downrange, for example the "786th yard".
The answer is that the bullet will make MORE than 4 1/2 complete revolutions during that yard.
This is because the translational velocity decays much more quickly than angular. As 4ked pointed out, the actual RPM of spinning is decreasing, its just that the velocity is decreasing much faster. So the relative rate of spinning (eg 1:8 initial) is increasing down range.