My problem with using big and powerful guns on animals is it destroys a lot of meat. In my opinion, a .243 does a lot of damage. Some guys use .300 mags and its way excessive.
And about the .243 shorts, I've never heard of a gun that uses them. But I seen a box of ammo at gander mountain. Weird store, carries a bunch of oddball stuff but can't even order 10 gauge shells.