More likely the barrel was painted by the previous owner, like I said, H&R hasn't made the BC Carbine since 2008. H&R does black oxide refinishes tho, so it could have been redone after the fact, it's not a standard accessory barrel finish tho, it would had to be a special request on the barrel order or aftermarket. My 45-120 BC barrel has a matte finish, but it was done my my gunsmith.
Tim