Cool, I don't have any big game rifles that weigh in that much. I can't help but think the weight would help with staying steady when shooting from field positions as well as help the recoil factor. Like you, I'm in my mid 40's and work out alot. I find that the lightest rifle I own-WBY lgtwt- is the toughest to shoot well from field positions (and the bench for that matter). The light whippy barrel makes it pretty muzzle light. I prefer a little bit of muzzle heaviness to help steady myself. just seems to "hang" better for me. If I get another "big bore" I am going to probably go for a rifle that has some weight to it. I actually think that this 375 rum xcr is the 2nd lightest big game rifle I own. I'd have to weigh them all to be sure but it sure feels light.
