Don't buy a rifle with the plan of a barrel swap in the future. How many of us have only one rifle?
I do like the 6.5x55 Swede but that's because I also have a couple Swedish Mausers. If that is something that interests him, and you want to get him an old m/38 Mauser as well, or perhaps you are part Swedish, then by all means. Unless you live in Alaska, a 6.5x55 might cover all your hunting needs with less pain on the shoulder. However if you are starting fresh and he has no interest in past relics, there are other options.
I do like the 6.5x55 Swede but that's because I also have a couple Swedish Mausers. If that is something that interests him, and you want to get him an old m/38 Mauser as well, or perhaps you are part Swedish, then by all means. Unless you live in Alaska, a 6.5x55 might cover all your hunting needs with less pain on the shoulder. However if you are starting fresh and he has no interest in past relics, there are other options.