30/06 rounds

[emmagee1917]

The US Army adopted the M1 AP round in 1934 . Due to problems they replaced it with the M1A1 AP in 1938 . Continuing problems lead to the acceptance of the M2 AP in 1939 . It was basicly a return to the M1922 AP that the M1AP replaced.
Early M2 AP had the extra cannelure to ID it as M2 . This continued till '41 or so . After that , the date on the case head ID'd it as M2 , and the extra cannelure was dropped.
Chris