Even when breaking in a custom barrel, I've gotten a lot of blue out of the barrel with the first shots. You actually want the manufacturer to shoot your gun. More is better. Henry claims to shoot/test their rifles with a full magazine before they ship and that's partially why, when you buy a Henry, it works right. Those first shots will leave a bunch of copper though. If somebody behind the counter took the gun out for a joy ride, they'd likely clean it inside and out, before selling it to hide things.