so how about M16A1??? they are over 50 years old.
I think you're mistaken. The originally issued M16 is over 50 years old this year (entered service via the U.S. Air Force in 1962). The M16A1 wasn't done until 1967.
It may be possible to acquire an M16 if there are any out there to be had as a C&R, but the A1 version still too young under the 50 year rule.
NRA Chief Range Safety Officer, Home Firearm Safety and Pistol Instructor
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