Q: On the receiver of the Colt Expanse rifle, the caliber is listed as “5.56MM” but on the barrel the caliber is listed as “5.56 NATO”. When logging on A&D and 4473, which caliber should be listed? Should we use the more specific one (5.56 NATO) or the one stamped on the lower receiver (5.56MM)?
View the answer to this and thousands of other questions in our client-only Support Center.
View Answer