5 inch/54 caliber Mark 42 gun

The 5"/54 Mk 42 is an automatic, dual-purpose (air / surface target) gun mount. It is usually controlled remotely from the Mk 68 Gun Fire Control System, or locally from the mount at the One Man Control (OMC) station. The self-loading gun mount weighs about 60.4 LT including two drums under the mount holding 40 rounds of semi-fixed case type ammunition. The gun fires 31.75 kg projectiles at a velocity of 2650 ft/s. Maximum rate of fire is 40 rounds per minute. Magazine capacity is 599 rounds per mount. The Mark 42 mount was originally equipped for two on-mount gunners, one surface and one antiaircraft, but the antiaircraft gunner position was scrapped later on when the increasing speed of naval aircraft made manual aiming of anti aircraft weapons impractical. The Mark 45 lightweight (22.1 LT) gun mount began replacing the Mk 42 mount in 1971 for easier maintenance and improved reliability in new naval construction for the United States Navy. • Illustration — Two of the eight turrets of the carrier Ranger firing, in 1961.

• Name — Mark 42 5"/54 Caliber Gun • Origin — United States • Type — Naval gun • Is Ranged — yes • Is Artillery — yes • Service — 1953–present • Used By — See users • Wars — Vietnam War Lebanese Civil War • Weight — 60.4 LT • Length — 9.652 m • Part Length — 6.858 m Rifling: 5.82 m • Cartridge — 127 x 835mm.R Conventional: 31.75 kg • Caliber — 5 in • Rate — As built/designed: 40 rounds per minute automatic Down-rated to 28 rounds per minute in 1968 • Velocity — 2650 ft/s • Max Range — • 25909 yd at +45° elevation • 51600 ft at +85° elevation • Recoil — 18.75 in • Elevation — • -15°/+85° Maximum elevation rate: 25°/sec • Traverse — • 150° from either side of centerline Maximum traversing rate: 40°/sec

• Illustration — Map with current ship operators with 5-54 caliber Mark 42 guns • United States • United States Navy • First used on Northampton • (later removed during upgrade) • and Truxtun * * * * * • Illustration — Side profile of the 5-inch gun from Brisbane; • Royal Australian Navy • (modified Charles F. Adams class); • Egyptian Navy • Damiyat-class frigate (ex-USN Knox-class frigates); • German Navy • (modified Charles F. Adams class); • Hellenic Navy • Ipiros-class frigate (ex-USN Knox-class frigates) • Kimon-class destroyer (ex-USN Charles F. Adams-class destroyer); • Japan Maritime Self-Defense Force * * * * *; • Mexican Navy • Ignacio Allende-class frigate (ex-USN Knox-class frigates); • Spanish Navy • (modified Knox class); • Republic of China Navy • Chih Yang-class frigate (modified ex-USN Knox class); • Royal Thai Navy • (ex-USN Knox-class frigates); • Turkish Navy • Muavenet-class frigate (ex-USN Knox-class frigates)