Ed technically any weapon that is proveably 50 yrs old or older. But the written word is always your best bet. If the ATF says it is C&R then no one can dispute it least of all Government. Keep up to date on those circulars they are always coming out with. Every so often there is another weapon added to the C&R list.Stuff used in Vietnam, and around that era starts coming into our realm Right now 1960 is the cut off.