You would be able to get some impressive velocities out of the Arisaka being the "king" of rifle strength! P.O Ackley did some pretty out there test & he couldn't blow one of these up from memory!
My father in-law had one made into a .243, sadly it was loaned many years ago - but never returned.
I reckon the .300 Savage would be great round to do on the action.
Certainly a challenge, but it is the action with the least parts - including a safety if I'm not mistaken!