| 3"/23 caliber gun | |
|---|---|
 A 3"/23-caliber gun being fired aboard theUnited States Navysubmarine chaserUSS SC-291 sometime between 1918 and 1920. | |
| Type | |
| 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 |
|
| Variants | Mark 9, 13, and 14 |
| Specifications | |
| Mass |
|
| Length |
|
| Barrel length |
|
| 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 |
|
The3-inch/23-caliber gun (spoken "three-inch-twenty-three-caliber") was the standardanti-aircraft gun for United Statesdestroyers throughWorld 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 23calibers long (barrel length is 3" × 23 = 69" or 1.75 meters.)[1]
Thebuilt-up gun with horizontalsliding 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).[2] Range was 10,100 yards (9235 meters) at 45 degrees elevation.[2] Ceiling was 18,000 feet (5500 meters) at the maximum elevation of 75 degrees.[2]
The 3"/23-caliber cannon was the first purposely designedanti-aircraft cannon to reach operational service in the US military, and was a further development of a 1-pounder cannon concept designed byAdmiral Twining to meet the possible threat from airships being built by various navies.[3]
A partially retractable version was mounted as adeck gun on the USL-class,M-1 (SS-47),AA-1 class, andO-classsubmarines.
WhenWorld War II began, the 3"/23-caliber gun was outdated, and surviving United States destroyers built during theWorld War I era that were armed with the 3"/23-caliber were rearmed with dual-purpose3"/50-caliber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.[2] Some major warships carried 3"/23-caliber guns temporarily while awaiting installation of quad1.1"/75-caliber guns.[2]
The 3"/23-caliber gun was mounted on:
