Roy,
Yea, I read the post about the 250 scenars. Makes me sort of re-think about even messin' with them. Especially if the SMK's are working so far. I don't have alot of history with them yet but I guess I'll stay where I'm at and tinker with something else. Didn't get the other powder anyhow.
I got a .375 RUM take off barrel off of Kirby myself. Some day I may want to shoot a really big bear and I'll just switch the barrel on my 300 RUM and try that. If not maybe I can trade it to someone for something I'l need.
Good luck on the project.