Big Game is a very good powder in the.375, particularly with 270-grain bullets. However, the Ramshot rifle powders don't tend to operate all that well until the load get up approaches 60,000 psi. Many "traditional" handloaders give up when starting loads don't group all that well, but if you keep adding powder the groups usually tighten up considerably.
Big Game is a great powder in many cases that have moderate capacity for their bore-size. It's a great powder, for instance, in the .30-06 with 150-grain bullets, easily capable of 3000+ fps with tiny groups. Also great in the .22-250, .220 Swift and .243 with lighter bullets. But usually you have to load it up to near the max powder charge listed to get the good results.
