I know they test fire, but I have NEVER heard of copper fouling in the barrel at the time of purchase. I'm thinking your local shop owner let somebody test fire the rifle. I would shoot it once then run a patch through the bore. see how blue it turns. most new factory barrels foul pretty bad for the first few shots during barrel break in, then they take longer and longer before they become fouled. not a foolproof method but you may get an idea. then again if its a real shooter and the throat and rifling look new you may be better off to keep it as you might get an unfired gun that won't group.