|Issued by: United States Navy|
|Type||Enlisted rating (Seamen)|
|Specialty||Small Arms, Torpedoes, Vertical Launching Systems (VLS), Ordnance, Gun Mount Systems, 5″ Gun Systems, and Magazine Sprinkler Systems|
The United States Navy occupational rating of gunner’s mate (GM) is a designation given by the Bureau of Naval Personnel (BUPERS) to enlisted sailors who either satisfactorily complete initial Gunner’s Mate “A” school training, or who “strike” for the rating by showing competence in the field of ordnance. When “striking” you do not need to be a seaman, but you do need to be one of the three undesignated rates; Fireman (FN), Seaman (SN), or Airman (AN). You can also “cross rate” to Gunner’s Mate. “Cross rating” is where you cross from your current rating to another rating of your choice if your ASVAB scores are high enough and the Navy has any open slots for that rate, for example; Information Specialist third class (IS3) can cross rate to a Gunner’s Mate, then that sailor becomes a Gunner’s Mate third class (GM3).
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, missile launchers and torpedoes 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.
A GM will specialize in weapons such as the M500 shotgun, M60 machine gun, M14 rifle, M2 Browning machine gun, M9 pistol, M11 pistol, M16 rifle, M240 machine gun, M203 grenade launcher, M79 grenade launcher, M1911 pistol, M1 Garand, Mk 19 grenade launcher, Mk 18 Mod 0 Carbine Rifle, 5″/54 caliber Mark 45 gun, M242 Bushmaster chain gun, Vertical launching system, Missiles, torpedoes, pyrotechnics, hand grenades, non-lethal weapons, force protection & anti-terrorism, as well as operating shooting ranges, armories, and the storage and issue of ammunition.
On February 26, 2007 the Chief of Naval Operations approved the merger of the gunner’s mate (GM) and torpedoman’s mate (TM) ratings into the GM rating. The move was made to leverage the strengths, knowledge, skills and abilities found in the two ratings to meet mission needs now and in the future.
“The training Sailors receive after basic training for their ratings on an apprentice level has been the same for both gunner’s and torpedoman’s mates,” said Senior Chief Torpedoman’s Mate Sherry Secrease of the Navy Personnel Command. “This makes the merger easier to accomplish.” 
The Gunner’s Mate rating is primarily surface warfare-based. Closely associated Naval occupational ratings are Fire Controlman (FC), Aviation Ordnanceman (AO), Weapons Technician (WT), Missile Technician (MT), Mineman (MN), and Machinist’s Mate (Weapons) (MMW). The Gunner’s Mate rating is one of the original ratings created as a result of the Naval Armament Act of 1797. The others include Boatswain’s Mate (BM), Quartermasters (QM) and Master-at-Arms (MA). The rating is also among the top five source ratings for enlisted Naval Special Warfare candidates.