Re: help
if you got a crony, buy a box of the hornady 150sst get your fps. measure the oal of a few shells, take apart a few shells also, weighing whatever powder is inside, measure the casings for trim length, etc.
start with the lower load, build it up likejgillam above, and if there are no signs of pressure, keep going up until you reach the fps your looking for, or when you start feeling uncomfortable safety wise, then find another powder.
should come close.
was stuffing 29 grains of aa2640 in a .223, (yikes) with a 40 gr. vmax. matched the velocity and results on paper to the factory stuff which is very good and flies at 3746 fps.
ammo / bullet / powder companies seem to stretch their numbers sometimes, and hardly ever match, also check to see the length of the test barrel from load data to load data, as that seems to differ also.
XHODZAX - don't forget that some bullets, although same weights, differ in length and changes your case capacity. CHANGES PRESSURES, fps, etc. can be compensated sometimes by altering oal, sometimes not.