I'm not a fan of either of those options. Having shot and owned both of them I would suggest a bolt action rifle for a first hunting gun. The semi-auto generally doen't promote the best first shot placment. The 30-30 is an good gun but how about something in a lower recoil round like a 7-08, or .243 ? I have taken over 30 deer with the .243. If you want a larger bullet go with the -08.
If you don't like those options. What about a nice .270 and use the managed recoil ammo by federal
http://www.chuckhawks.com/federal_low_recoil.htm I've shot it and it's about the same as a .243 for recoil. Then your son can continue to use it for everything from Whitetail, Mulies, Elk, etc. It's a great investment in any type of hunting. You can pick up a good used .270 fairly inexpensively with a scope mounted on it and case.
I hope he has good luck this fall!