I'm very surprised that nobody mentioned the 25-06. IMO better than either the 243 or 7mm-08. More energy that the first, quite a bit less recoil than the 2nd. Still good for varmints like 'yotes, but can move up to mulies, black bear. Able to crack bone and keep going better than the 243.

It's one of my favorite calibers...and I don't even own one Check it out, I'm guessing your boy would be very happy with it . Good luck.