Firearms Curios or Relics List - U S Department of Justice - Bog

Firearms automatically attain C&R status when they are 50 years old. Any firearm that is at least 50 years old, and in its original configuration, would qualify as a C&R firearm. It is not necessary for such firearms to be listed in ATF's C&R list. Therefore, ATF does not generally list firearms in the C&R publication by virtue of their age. However, if you wish for a classification of your particular firearm under categories (b) or (c) above and wish your item to be listed, you may submit the weapon to the Firearms Technology Branch (FTB) for a formal classification.