| 3 Inch / 21 Caliber Field Gun | |
|---|---|
| Type | |
| Place of origin | United States | 
| Service history | |
| Used by | |
| Production history | |
| Designed | 1874 | 
| Produced | 1875 – | 
| Specifications | |
| Mass | 384 pounds (174 kg) | 
| Length | 69.6 inches (1.77 m) | 
| Barrel length | 64.3 inches (1.63 m) bore (21 calibres) | 
| Shell | 13 pounds (5.9 kg) (projectile) | 
| Caliber | 3-inch (76 mm) | 
| Breech | Fletcher breech mechanism | 
| Recoil | hydraulic recoil piston | 
| Carriage | Wheeled | 
| Rate of fire | 8 – 9 rounds per minute | 
| Muzzle velocity | 1,150 feet per second (350 m/s) | 
| Effective firing range | 5,000 yards (4,600 m) at 19.5° elevation | 
The 3"/21 caliber gun (spoken "three-inch-twenty-one-caliber") was a field gun for United States Navy and United States Marine Corps. They were a simple horse-drawn artillery gun that were mostly used by the Marines. The guns have also been described as Boat Guns but information on type of mounts has not been found.[1]
Description
The Mark 1 was intended as a support gun for landing operations. It was of simple monobloc construction with a Fletcher breech mechanism with down swinging carrier, and used a hydraulic recoil piston that was screwed onto the gun directly. It most likely used bagged ammunition with a 13 pounds (5.9 kg) projectile at a velocity of 1,150 feet per second (350 m/s). Range was 5,000 yards (4,600 m) at 19.5 degree s of elevation.[1]
Surviving pieces
Guns No. 5 and 6, built in 1875, had been restored and were located in St. Clair, Pennsylvania as of 2004.[1]
References