I bought magnum primers because I was not able to find large rifle. I have varget and IMR-4198 on hand any one use any of this combo to point me in a direction. I am going to start small and work my way up with Varget again for my AR-10.
Go for it. Just drop back a bit on the powder charge and work back up. I have a few .308 loads the seem to have a definite preference for mag primers. One is with BLC-2 , which is fairly common with many ball powders.