These were used for anti-aircraft and also in shore batteries. They fired 20 rounds per minute with a range over 8 miles. They were 50-caliber and had a 3-inch barrel that was 12 and a half feet long. They was mounted on practically every Navy ship.
1943
The 3-inch / 50-Caliber Deck gun (versions Mk 2 thru Mk 22) was a staple on board a variety of US Navy vessels and could be seen proudly mounted on everything from the "Porpoise" through "Gato" classes of submarines to LCSs & Liberty ships, as well as battleships, cruisers, destroyers, and escorts. These dual purpose Mark guns were primarily used for anti-aircraft protection. They were also used in shore batteries. The M22 could fire 45 rounds per minute with a range of 14,600 yards. Many ships were upgraded to the 3-inch / 50-caliber guns by the end of the war in order to repel kamikaze aircraft, which could fly through damage inflicted upon them by smaller anti-aircraft weapons.
The earliest versions of the gun were deployed in the 1890s.
The M22 were installed on ships from 1943 to 1944, and remained in service on some Navy ships until 1994.
- Weight. 7,500 pounds
- Barrel Length: 12 feet 6 inches
- Bore diameter: 3 inches (76 mm)
- Rate of fire: 20 rounds per minute
- Muzzle Velocity: 2,700 feet per second
- Maximum range: 14,600 yards
- Crewed by a company of 7
3-inch/50-caliber gun
WIKIPEDIAThree Inch Fifty Caliber
In United States naval gun terminology indicates the gun fired a projectile 3 inches in diameter, and the barrel was 50 calibers long. Different guns identified by Mark numbers of this caliber were used by the U.S. Navy and U.S. Coast Guard from 1900 through to 1990 on a variety of combatant and transport ship classes.During the final year of the Second World War, it was found that multiple hits from Oerlikon 20 mm cannon and Bofors 40 mm guns were often unable to shoot down high-speed Japanese kamikaze aircraft at short ranges before they hit Allied ships; the 3-inch/50 caliber gun was adopted as a more powerful replacement for these weapons.
The 3-inch/50 caliber gun (Mark 22) was a semiautomatic anti-aircraft weapon with a power-driven automatic loader and was fitted as single and twin mounts. The single mount was to be exchanged for a twin 40 mm antiaircraft gun mount, and the twin 3-inch/50 for a quadruple 40 mm mount, on Essex-class aircraft carriers, and Allen M. Sumner and Gearing-class destroyers. Although intended as a one-for-one replacement for the 40 mm mounts, the new 3-inch (76 mm) mounts were heavier than expected, and on most ships, the mounts could only replace Bofors guns on a two-for-three basis. The mounts were of the dual purpose, open-base-ring type and the right and left gun assemblies were identical. The mounts used a common power drive that could train at a rate of 30 degrees/second and elevate from 15 degrees to 85 degrees at a rate of 24 degrees/second. The cannon was fed automatically from an on-mount magazine which was replenished by two loaders on each side of the cannon.
With proximity fuze and fire-control radar, a twin 3-inch/50 mount firing 50 rounds per minute per barrel was considered more effective than a quad Bofors 40 mm gun against subsonic aircraft.
The 3-inch/50 was standard-issue on at least 63 classes of ships that have a strong association with World War II. The total number of vessels amounts to
- 10 light cruisers
- 119 submarines
- 498 destroyer escorts and frigates
- 1110 patrol boats, mine sweepers and submarine chasers
- 161 landing craft / amphibious assault ships
- 116+ auxiliaries
These Deck Guns were mounted on practically every Navy ship. They were used for anti-aircraft and also in shore batteries.