I would guess it would be fairly easy, but why would you do it other than to have something unusual? There is tons of 7.62/54 brass, surplus stuff is cheap, you can buy surplus ammo, pull the bullets and load up anything you like in them for the price of a primer and bullet. They do have an odd controled feed system that may be a slight problem if you change brass size much and doing anything with a scope or a good trigger is a real pain. If someone ever figures out something to good to make out of them they will probably make a few bucks. Larry