Even 01 dealers do not need to enter antique firearms in their books.
But for general information, a firearm designated as an antique, even if it uses non-fixed ammo and an old type ignition system (flintlock, caplock, wheelock, matchlock) is still a weapon under the laws regarding carrying weapons and in laws about armed robbery, assault with a deadly weapon, etc.
So if someone shoves a snaphaunce in his belt and goes out to stick up the local liquor store, he can't plead that it is not deadly weapon or that he wasn't armed.
Jim