James, buds doesn't test fire firearms, they don't even open the box. I know alot of manufacturers test fire firearms to make sure they function properly before shipping. Another thing it might be from is the manufacturing process leaves residue behind that can make it look fired. I've bought quite a few new firearms that have looked used. Drilling out the barrel leaves metal shavings behind Wich can look like burnt gun powder residue. So don't believe it's anything to worry about. Just give it a good cleaning and some lube and fire away. Hope this helps.

James, Bud's does not open the box or test fire the gun. If it was test fired, it would be from the factory. I would contact Mossberg direct at (203) 230-5300, 8AM-4:30PM EST Mon-Fri.

James, no Sir they are not supposed to be but who knows. They are test fired at the manufacturer but nothing stops anyone at a retailer from doing so. I would clean it and give it a good inspection and if nothing excessive, carry on. Cheers and stay safe!