He's hunting brown bear, a lightweight rifle in a small caliber is not appropriate. A .375 is appropriate but not less than 9lb for a 74 year old. The ideal weight for a 7-08 or .270 is less than the ideal weight for a .375. If he were younger he could possibly get away with an 8 1/2 pound .375. Also, if you are lean and fit, losing bodyweight might actually be detrimental as the weight you lose would consist mainly of muscle mass and that will make you weaker. However, if you are carrying a bit of excess weight (fat), losing 5 lbs would be very beneficial. I was carrying medium weight rifles around for decades and it wasn't really an issue (except that they are more awkward) until I started to carry a 7lb rifle. Then all of a sudden, the 8 1/2 pound rifles seemed heavy. What I am saying is that there is benefit in carrying a light weight rifle but also some of the benefit is just in our heads. When I had to carry a 10 1/2 pound rifle around again, it was only "heavy" for the first day, then after that I got used to it and it wasn't such an issue. But climbing up mountains you really notice the added weight. I'd rather carry a 20 lb pack than a 10 lb rifle.
