I got my wife a new remington 30-06 three years ago and immediately began to use the managed recoil rounds in it and they were great. I would not question using them at all. I would get the gun you want and never look back. There is no need to get a smaller caliber or shoot lighter loads or anything. The managed recoil rounds are good to 225 yards, the point of impact is consistant, and the bullets have good expansion.

The recoil actually is about that of a 30-30 to a.243 for any of the loads.

If he needs a smaller gun , like a model 7 or a m77 compact, then Get him a .308 and shoot managed recoil until he is big enough to handle full loads. That gun would last a lifetime.

If he is big enough for a full sized gun, either the .270 or 30-06 is fine.

The only thing to note is that the managed recoil rounds powder charge is not big enough to cycle the action of a semi-auto gun. So you are limited to bolt actions or single shots. But that is not necessarily a bad thing, just simply something to be aware of.

God bless