Any 30-06 should be able to get 3,000 fps with a 180 grain bullet--once. <img src="/ubbthreads/images/graemlins/grin.gif" alt="" />
If you're getting 2850 (allowing an extra 50 fps for the extra 2" of barrel), at 58,000 PSI, and increase the charge 3 grains, you'll be at ROUGHLY 65,000 PSI, still 5 KPSI short of the point where normal pressure signs show up.
As Dutch once succinctly observed: Muzzle velocity is a pressure sign.
There are no magic "fast" or "slow" barrels. Acceleration = Force/mass. Speed is Vinitial + the integral of force over time. Force is pressure times the area of the base of the bullet - friction. Getting bullet speed without pressure violates the Law of Conservation of Energy.
You're right Denton, there are no magic barrels--but there are fast and slow barrels. The benchrest guys, whose methods and equipment are far more "precise" than our sporter rifles, demonstrate it often.
Rough bores seem to create different friction than a tight, smooth bore--in both cases it's friction, but can produce different pressures, or at least different results. Constrictions in the bore--dependent of where the constriction occurs, can produce different velocity.
By changing the shape of the pressure curve--but not changing the pressure peak--we can often increase/decrease velocity
Maybe more pertinently, although we can land a man on the moon, we do not understand all the factors taking place inside a chamber/bore of a rifle. Much of what we do have some knowldge of is through indirect measurements/observation.
You are right--pressure equals velocity, but there are factors that qualify that.
I have two 30-06AI's with 22in barrels--both have had fair number of loads ran through Oehler Ballictics Labs. I ran 180gr X's a little over 2900fps and 180gr Partitions right at 2900fps. The loads are warmish, the occasional shot bumps up against the SAAMI max in warm weather, but the average of the shot to shot pressures is under max enough to keep me comfortable.
Casey
