Per the Bureau of Alochol, Tobacco and Firearms,
By statute, the prohibitions relating to semiautomatic assault weapons and large capacity ammunition feeding devices expired on September 13, 2004. As a result, certain sections of the Gun Control Act, 18 U.S.C. Chapter 44, and its implementing regulations, 27 CFR Part 478, are no longer in effect.
Of course YMMV depending on whether you live in a girlie-man state such as California that has its own “assault” weapons ban.