Hoorah for the old 7x57. If anything, that story proves that the right bullet and proper placement are more important than size and velocity in a most cases. Unless you are hunting game at hellacious distances or if you are looking down the barrel at teeth and claws the old standard calibers will probably work best. The one gun shooter will be best served by the old .30.06, ammo wont break the bank and can be found in every gun shop. It will take down everything on this continent and most others, except the very large bears.
My 2 cents worth.

El Lobo