The definitions of Antiques ARE NOT the same under the Gun Control Act of 1968 and the National Firearms Act. A pre-1899 manufactured Antique not regulated by the Gun Control Act of 1968 MAY BE considered a Firearm by the National Firearms Act and regulated by it.

Short barreled shotguns are regulated by the National Firearms Act if they do not meet THAT Act's definition of an Antique.