I hate those big box stores, but at my HD the black pipe have plastic caps on the ends to help prevent that. Though those threads seem to have been cut bad to begin with. Black pipe or any pipe in general has a tapered thread unlike a bolt thread. So you should never have a problem starting them, just a problem having it tightened tight in the right direction. If you return it just grab a fitting in the same dept and try both ends. Good luck.