That K31 is just as good as any thirty cal commonly used for hunting, like 30-06 or .308. You can always, easily, get a St. Marie scope mount, which doesn't damage the gun, if you want to scope it. I have plans to hunt with a K31 and take a deer.
While reloading might seem like a formidable hobby, if you were only interested in reloading for a single caliber, 7.5x55 Swiss, it is pretty easy. I just mention that because of the lead free issue.
Myself, I would take a pass on the 30-30. I think there are so many other better and more useful rounds out there; 243, 25-06, anything in 6.5 mm, 270, and the venerable 30-06.