There is nothing wrong with the 6mm barrel that is on the gun, only had a couple hundred rounds through it. I already have 2 other 6mm's a couple .243's built for 500 yard capability, a .264 win and a .338 win for 1000 yard dog and deer shooting all topped with mark 4's, problem is the 264 gets to hot and eats a barrel every year. I'm kind of looking for somthing that might take it's place. my smith is not to keen on the .284 ( he don't have the newer short throat reamer) what about a 7x57 ackley? anybody now anything about it?