14-inch/50-caliber gun

14"/50 caliber gun
New Mexico-class battleship USS Idaho (BB-42) in 1920, showing six 14"/50 caliber guns
Type	Naval gun
Place of origin	United States
Service history
In service	1918–1956
Used by	US Navy
Wars	World War II
Production history
Designer	Bureau of Ordnance
Designed	Mark 4: 1916 Mark 7: 1930 Mark 11: 1935 Mark B: 1937
Manufacturer	U.S. Naval Gun Factory
No. built	Mark 4 Mod 0: 39 (Nos. 82–120) Mark 4 Mod 1: 80 (Nos. 121–200)
Variants	Marks 4, 6, 7, 11 and B
Specifications
Mass	179,614 lb (81,472 kg) (with breech)
Length	59.5 ft (18.1 m)
Barrel length	700 in (18 m) bore (50 calibers)
Shell	Mark 8: 1,402 lb (636 kg) Armor-piercing (AP) AP Mark 16: 1,500 lb (680 kg) AP HC Mark 19: 1,275 lb (578 kg) High explosive (HC)
Caliber	14-inch (356 mm)
Recoil	48-inch (1,220 mm)
Elevation	New Mexico-class: -5° to +15° (later increased to 30°) All other: -5° to +30°
Traverse	306° max 297° min
Rate of fire	Marks 4, 6, 7, 11: 1.75 rounds per minute Mark B: 2 rounds per minute
Muzzle velocity	Mark 4 and 6: 2,800 ft/s (850 m/s) Marks 7, 11, and B: 2,700 ft/s (820 m/s) AP Marks 7, 11, and B: 2,825 ft/s (861 m/s) HC Reduced charge: 1,935 ft/s (590 m/s) AP Reduced charge: 2,065 ft/s (629 m/s) HC
Effective firing range	25,000-yard (22,860 m) at 15° elevation HC
Maximum firing range	36,800 yd (33,600 m) at 30° elevation AP

The 14"/50 caliber gun was a naval gun mounted on New Mexico and Tennessee-class battleships. These ships also featured the first "three-gun" turrets, meaning that each gun in each turret could be "individually sleeved" to elevate separately (however, they could be linked so they would elevate as a unit, similar to the triple turrets on other Navy ships). The 14"/50 caliber guns were designated as Mark 4 and 6, with later versions known as Mark 7, 11, and B. These guns were more powerful than the main gun mounted on the previous three classes of US battleships (the New York, Nevada and Pennsylvania classes), the 14"/45 caliber gun.^[1]