Re: .308 Norma Mag
I have a 30-338, which is pretty much the same thing.
I use IMR4831 at 66.0gr. with a Berger 190 VLD. I seat them .015 into the lands and get 2960 with this load. I have been to 3000 easily but groups opened up so I backed off.
By the way I have a 30", 10 twist barrel.