[tnbowhunter]

I've owned them both and have killed many deer with both chamberings. I also shoot and own a 260 which is also based on the 308 case.

Recoil wise the 243 will have a little less recoil if you shoot lighter weight [read varmint] bullets. It would be an excellent caliber for your son to practice with using these lighter weight bullets particularly in the 55-70 grain range. It would be an easy matter to step up to a hunting weight bullet [95-105 gr] when deer season rolls around. I can guarantee he will never feel the increase in recoil shooting at a deer or other game. That said I think the 7mm-08 or the 260 is a better over all caliber because you will get a little more penetration and a bigger wound channel on a marginal hit.

Any of the three will kill a deer, especially the size deer that you and I hunt [probably way under 150lbs] with a well placed bullet. If I were hunting deer out to 200+ lbs. I would choose the 7mm-08 or the 260 hands down over the 243 just because you can shoot a heavier bullet.

My daughter and wife both killed their first deer with a 243 in a Remington Mdl. 7. The Mdl. 7 wouldn't be my first choice for a long range rifle because of the short barrel but it is still good out to 100+ yards. My daughter still shoots the 243 but my wife now uses the 260 which is also a Rem. Mdl. 7. The Mdl. 7 also comes in a youth size and all you have to do when your son grows would be to switch the stock out for a regular size stock.