18 inch barrel - Remington 18inch BS 870 Express Extra Barrel

The barrel came faster than expected. Ot was weird when I opened the box though. The barrel was heavily oiled and when I wiped it down there was a ton of dirt residue on the barrel as if it was used before. I'm not sure if this is true and there is no way I can prove it. Also fyi, barrel isn't threaded for a choke. Havent had chance to shoot it yet but I dodondodont expect any problems with it.