5"/50 caliber gun

Chattanooga, 5"/50 caliber deck gun, probably port side forward.
Type	Naval gun Coastal gun
Place of origin	United States
Service history
In service	1904
Used by	United States Navy
Wars	World War I World War II
Production history
Designer	Bureau of Ordnance
Designed	1900
Manufacturer	U.S. Naval Gun Factory
No. built	Mark 5: 87 (Nos. 200–286) Mark 6: 64 (Nos. 293–356)
Variants	Mark 5 Mods 0–3, Mark 6 Mods 0–2
Specifications
Mass	Mark 5: 10,294 lb (4,669 kg) (with breech) Mark 6: 10,550 lb (4,790 kg) (with breech)
Length	Marks 5 and 6: 255.65 in (6.494 m)
Barrel length	Marks 5 and 6: 250 in (6.4 m) bore (50 calibers)
Shell	Mark 5: 60 lb (27 kg) armor-piercing Mark 6: 50 lb (23 kg) armor-piercing
Caliber	5 inches (127 mm)
Elevation	Mark 9: −10° to +15° Mark 12: −10° to +25°
Traverse	−150° to +150°
Rate of fire	6–8 rounds per minute
Muzzle velocity	50lb:3,000 ft/s (910 m/s) 60lb:2,700 ft/s (820 m/s)
Maximum firing range	19,000-yard (17,374 m) at 25.3° elevation

The 5"/50 caliber gun (spoken "five-inch-fifty-caliber") was the first long barrel 5-inch gun of the United States Navy and was used in the secondary batteries of the early Delaware-class dreadnought battleships, protected cruisers, and scout cruisers and refit the armored cruiser New York, and the New Orleans-class protected cruisers. They would go on to be used on cargo ships, store ships and unclassified auxiliaries during World War II as well as in emergency coastal defense batteries.

Design

The Mark 5, Nos. 200 – 286, was a 50 caliber naval gun of a simplified construction by combining the breech piece along with the chase hoop into one long tube that was shrunk on from the muzzle. Mod 1 was a Mod 0 gun that was relined with a conical nickel-steel liner and an additional gun-steel chase hoop that extended to the muzzle that was secured by a nickel-steel locking ring. Mod 2, gun No. 280, had a slightly different liner with Mod 3, gun No. 245, was a Mod 0 gun with its gun-steel tube replaced with a nickel-steel tube with a gun-steel chase hoop added that extended all the way to the muzzle. The Mod 3 gun had a longer chase hoop and shorter jacket compare to Mods 1 and 2.

The Mark 6, gun Nos. 293–356, was the bag-ammunition equivalent to the Mark 5 gun. Mod 0, Nos. 323-356, had a single jacket constructed of nickel-steel, that replaced the jacket, chase hoop and locking ring of the Mark 5. Mod 1, Nos. 293–306 and 308, was built of gun-steel with a chamber of a different design with some external differences to fit it onto differnet mountings. The Mod 2, Nos. 307 and 309–322, had the same chamber as the Mod 0 but was otherwise almost identical to the Mod 1.

Naval Service

Ship	Gun Installed	Gun Mount
USS Delaware (BB-28)	Mark 6 Mod 0: 14 × 5"/40 caliber (Nos. 343–356)	Mark 9 and 12
USS North Dakota (BB-29)	Mark 6 Mod 0: 14 × 5"/40 caliber (Nos. 329–342)	Mark 9 and 12
USS New York (ACR-2)	Mark 6 Mod 1: 10 × 5"/40 caliber (Nos. 295–304) (1907 refit)	Unknown
USS Denver (C-14)	Mark 5: 10 × 5"/40 caliber	Unknown
USS Des Moines (C-15)	Mark 5: 10 × 5"/40 caliber	Unknown
USS Chattanooga (C-16)	Mark 5: 10 × 5"/40 caliber	Unknown
USS Galveston (C-17)	Mark 5: 10 × 5"/40 caliber	Unknown
USS Tacoma (C-18)	Mark 5: 10 × 5"/40 caliber	Unknown
USS Cleveland (C-19)	Mark 5: 10 × 5"/40 caliber	Unknown
USS Chester (CS-1)	Mark 6 Mod 0: 2 × 5"/40 caliber (Nos. 323–324)	Unknown
USS Birmingham (CS-2)	Mark 6 Mod 0: 2 × 5"/40 caliber (Nos. 325–326)	Unknown
USS Salem (CS-3)	Mark 6 Mod 0: 2 × 5"/40 caliber (Nos. 327–328)	Unknown
USS New Orleans (CL-22)	Mark 5: 10 × 5"/40 caliber (1904 and 1907 refits)	Unknown
USS Albany (CL-23)	Mark 5: 10 × 5"/40 caliber (1904 and 1907 refits)	Unknown

The 5"/50 caliber gun was used on cargo ships, store ships and unclassified auxiliaries during World War II.

External links

• Bluejackets Manual, 1917, 4th revision: US Navy 14-inch Mark 1 gun