You might also look into a Limbsaver recoil pad. I think it made a night/day difference on my shoulder, with my 300 and 338 RUMs. On both my Rem 700 with composite stock and the Stainless Stalker A-Bolt, the pads were drop in fits. Took about ten minutes to replace both.
I also load a 165gr SST for deer hunting, at 30-06 speeds. Kind of following the Remington sales campaign of three power levels for the 300RUM. One approximates 30-06, two equals the 300WinMag and three is full power Ultra Mag.