Every Remington 700 and Browning A bolt stainless stalker I had with the addition of a good muzzle break, bedded, barrel freefloated would shoot tiny groups with 120,140, and 150g bullets. Current rifle shoots the 162g SST(very tough bullet) at 3130 fps with Retumbo and 215's, bullet touching the lands(bug hole three shot groups).
I really don't know the reason to improve the 7 RM unless you want to go to a Mashburn, then 160's at 3200 are ho humm(thank you Bob!)
