Figured I'd chime in here with a bit of legalese as the bit about seemed incorrect to me. So I looked it up:
The term "firearm" means (A) any weapon (including a starter gun) which will or is designed to or may readily be converted to expel a projectile by the action of an explosive; ( the frame or receiver of any such weapon; © any firearm muffler or firearm silencer; or (D) any destructive device. Such term does not include an antique firearm.
18 U.S.C. sec. 921(a)(3).
Yup...unless it's an antique, it's a firearm. That's why I protect my shop with sharp forged objects :)