allenday,
Best rule of thumb for reloading: there are no rules of thumb.
My personal rule of thumb for large magnum cases is to fill them near capacity with a slow burning powder and start there. IMR and H4350, by many reports I read, and IME tops out pressure wise in such large cases before it tops out in velocity potential, accuracy not withstanding as that varies rifle to rifle as well.
I never tell anyone a particular powder/bullet combo will assure them of accuracy. I will relate my personal experiences.
As a "rule of thumb" the same powder charge behind the same bullet will produce near like velocity from the same length bbl with like pressures, thought not identical...accuracy will not necessarily be the same.
My current load: 74grs R-19, 180 Horn. Interlock, Fed 215, Rem Brass, seated to just touch the lands. 3150fps, and consitent 1" 3-5 shot groups at 100 yards.
Last edited by .280Rem; 03/01/06.
