3-inch/23-caliber gun

The 3-inch/23-caliber gun (spoken "three-inch-twenty-three-caliber") was the standard anti-aircraft gun for United States destroyers through World War I and the 1920s. United States naval gun terminology indicates the gun fired a projectile 3 inches (76 mm) in diameter, and the barrel was 23 calibers long (barrel length is 3" × 23 = 69" or 1.75 meters.)

3"/23 caliber gun
A 3"/23-caliber gun being fired aboard the United States Navy submarine chaser USS SC-291 sometime between 1918 and 1920.
Type	Naval gun Anti-aircraft gun
Place of origin	United States
Service history
In service	1913—1946
Used by	US Navy
Wars	World War I World War II
Production history
Manufacturer	Bethlehem Steel (Mark 11) Driggs-Schroeder (Mark 13) Poole Engineering and Machine Company (Mark 14)
Variants	Mark 9, 13, and 14
Specifications
Mass	Mark 9: 749 pounds (340 kg) (with breech) Mark 13: 531 pounds (241 kg) Mark 14 Mod 0: 593 pounds (269 kg) (with breech) Mark 14 Mod 1: 658 pounds (298 kg) (with breech)
Length	Mark 9: 77.05 inches (1.957 m) Mark 14: 79 inches (2.0 m)
Barrel length	Mark 9: 69 inches (1.8 m) bore (23 calibres) Mark 14: 71 inches (1.8 m) bore (23.5 calibres)
Shell	16.5 lb (7.5 kg) 76.2x234 mm R
Caliber	3-inch (76 mm)
Elevation	-15° to +65° or +75°
Traverse	365°
Rate of fire	8 – 9 rounds per minute
Muzzle velocity	1,650 feet per second (500 m/s)
Effective firing range	8,800 yards (8,000 m) at 45.3° elevation (WW I) 10,100 yards (9,200 m) at 45° elevation (WW II) 18,000 feet (5,500 m) at 75° elevation (AA)

Description

Plan and left elevation diagrams

The built-up gun with horizontal sliding breech block weighed about 531 pounds (241 kg) and used fixed ammunition (case and projectile handled as a single assembled unit) with a 13-pound (6 kg) projectile at a velocity of 1650 feet per second (500 m/s). Range was 10,100 yards (9235 meters) at 45 degrees elevation. Ceiling was 18,000 feet (5500 meters) at the maximum elevation of 75 degrees.

History

The 3"/23-caliber cannon was the first purposely designed anti-aircraft cannon to reach operational service in the US military, and was a further development of a 1-pounder cannon concept designed by Admiral Twining to meet the possible threat from airships being built by various navies.

A partially retractable version was mounted as a deck gun on the US L-class, M-1 (SS-47), AA-1 class, and O-class submarines.

When World War II began, the 3"/23-caliber gun was outdated, and surviving United States destroyers built during the World War I era that were armed with the 3"/23-caliber were rearmed with dual-purpose 3"/50-caliber guns. Where there was no air threat during World War II, the 3"/23-caliber gun was employed in the surface-to-surface role for use against submarines, and was mounted on submarine chasers, armed yachts, and various auxiliaries. Some major warships carried 3"/23-caliber guns temporarily while awaiting installation of quad 1.1"/75-caliber guns.

The 3"/23-caliber gun was mounted on:

• AA-1-class submarines
• Active-class patrol boats
• Aylwin-class destroyers
• Caldwell-class destroyers
• Colorado-class battleships
• Clemson-class destroyers
• Dubuque-class gunboats
• Florida-class battleships
• Klondike-class destroyer tenders
• L-class submarines
• USS M-1 (SS-47)
• O-class submarines
• PGM-1-class motor gunboat
• SC-1-class submarine chasers
• SC-497-class submarine chasers
• Wickes-class destroyers

References

• Campbell, John (1985). Naval Weapons of World War Two. Naval Institute Press. ISBN 0-87021-459-4.
• Fahey, James C. (1939). The Ships and Aircraft of the U.S. Fleet, War Edition. Ships and Aircraft.
• Fairfield, A.P. (1921). Naval Ordnance. The Lord Baltimore Press.
• Lenton, H.T.; Colledge, J.J. (1968). British and Dominion Warships of World War II. Doubleday and Company.
• DiGiulian, Tony Navweaps.com 3"/23 caliber gun