The new Lyman manual show the best load to be with RX-22 Starting load 58.5 gr Max load 65.0 gr. 2826 fps. Many other combinations would also work. Its a trial and error thing to find the best load. I like the data in the Lyman manual and use it for most of my loading.
Worked up a load lastyear for a friend 200 Ab/300wsm underIMR7828 and it produced very nicely for him. I won't give youhis charge as it is slightly over the published max in a couple manuals but was safe in his rifle. Nosler 5th suggests IMR7828 64-68gr under 200 gr. They indicate the 7828 at max load of 68gr was the most accurate they tested withLR Primers. In this case we also found large rifle primers work best with both RL22 and IMR7828. The RL22 produced slightly higher MV with comparable loads but also grouped larger in his rifle.
Either powder would beexcellent places to start (BTW Nolser 5th gives 63-67gr for RL22 under 200gr bullets).
200 grain Accubonds in a 300 WSM???
