I am looking to build a load using RS Mag powder in my .300 WSM. I realize this is not a preferred powder for this cartridge as it is generally too slow. I will be using it in a Winchester 1885 with a 28" barrel, and pushing a 208 GR A-Max or the new 210 GR. Accubond Long Range. Hopefully the added barrel length and bullet weight will make this more suitable. I would use 4831sc, but can't find any right now.
Thoughts?