Gunner's Mate Rating
The United States Navy occupational rating of Gunner's Mate (abbreviated as GM) is a designation given by the Bureau of Naval Personnel (BUPERS) to enlisted members who either satisfactorily complete initial Gunner's Mate 'A' school training, or who 'strike' for the rating as a deck seaman by showing competence in the field of ordnance.
The Gunner's Mate 'A' school is held at Naval Training Center Great Lakes, Illinois. While the school was originally very hands-on, it is now primarily conducted through self-study computer based training (CBT). The training focuses on the operation, maintenance, and troubleshooting of Naval guns and missile launchers as well as a strong emphasis on basic explosives, guidance and tracking systems, small arms, Naval ammunition classification, and safety. Upon completion of this basic training, enlisted members often continue on to a specialized 'C' school, where they learn a particular weapons system.
The Gunner's Mate rating is primarily surface based. Closely associated Naval occupational ratings are Fire Controlman (FC), Torpedoman (TM), Aviation Ordanance Specialist (AO), Weapon's Technician (WT), and Mineman (MN).