What do you guys recommend??

Recently bought a stock for my .308 Axis. That thread can be seen here: http://www.savageshooters.com/showth...432#post384432

I now have an extra stock of either action (.308 went on Boyd w/ long action mag). I already have a .223/5.56NATO 1:8. I have an almost 18 y/o that wants to get started distance shooting/hunting too. What caliber would you build out if you were in my boat? I'm also not opposed to not building and selling off one of the stocks. Thx in advance.