I think the Savage upper is about 1943 and probably the AO lower also. The AO lower will be 1928A1 as my AO upper (Savage lower) is in the 45,000 range and is a 1928A1, when a 1928 was made into a 1928A1, they added the A1 after the 1928 but the serial number ceased to be central to the above text so its quite easy to determine if a body was once a 1928 or not.
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