20-mm Automatic Gun M1 and 20-mm Aircraft Automatic Gun AN-M2 — TM 9-227

This manual is published for the information and guidance of using arms and services. It contains information of a technical nature required by the personnel of the Army and Navy for the identification, use, care, and preservation of the 20-mm Automatic Gun M1 and 20-mm Aircraft Automatic Gun AN-M2, and of the accessories and ammunition used therewith .