Hunting woodchucks with a 22 has been some of the most fun I've ever had hunting. Admittedly, I don't do it anymore but I'm old and lazy now, so I let the bullets do the "walkin"
Tell him to start there.
As for loading the 30-30 for it, sure you can. If you want to load single rounds instead of feeding from the magazine continuously, you could even use high-BC pointed bullets. Hitting them at 300 is just a matter of knowing wind/trajectory and making the clicks on the scope.