Prices being what they are, it's cheaper to buy a few extra barrelsMil spec. Chrome lined barrels should have a service life of 40 to 50 thousand rounds. The military would go broke swapping barrels at 10k rounds. I used to be cheap, and buy shitty ammo. But for just a little more money, you get a lot more accuracy and reliability and a much longer service life out of your weapons.
But it's also nice to shoot better than 4 moa