I was testing accurate Retumbo ,mag pro, H1000, and ramshot magnum in my wildcat 7STW. They were all good. Mag Pro was the eventual winner for what I had. Ramshot magnum is a good powder for heavy for cal rounds and longer barrels.
I load for a friends 338 win. It uses faster type powders like Ramshot hunter or reloader 19 as the go to powders