I have a 30-06 that is extremely finicky about what it will shoot. It's glass bedded in solid, and everything is torqued correctly, but it is basically a 3" @ 100 yd gun with with a wide variety of powders and bullets. I've tried 4350, 4831, Ramshot Hunter and Big Game, Speer, Hornady, Nosler, Barnes, 165 gr, 180 gr, 200 gr.... You get the idea. The only exception (and the reason I keep trying) is factory loaded Winchester Supreme 180 gr Accubonds. Those particular loads are sub 1" all day long and today I managed a 1.1" group @ 200 yds. Unfortunately, they are $45/box, so practice is kind of expensive. Plus I much prefer to load my own.
The loads are obviously Winchester brass, Winchester primers and Nosler Accubonds, but I'm stumped on the powder. I pulled one apart and it is stuffed with a 57 grs of a ball power. As a general description, the grains are about 50% larger in size that the Ramshot powder I have and they are slightly flattened. I'm speculating that its W760/H414, but don't have any of that powder to compare it too. Does the "slightly flattened" description match W760?
This is the 200 yd groups I'm trying to duplicate. Anybody have any ideas on what Winchester might have used for the powder?