| 5"/31 caliber Mark 1 Naval Gun | |
| Origin: | United States |
| Type: | Naval gun |
| Is Ranged: | YES |
| Is Artillery: | YES |
| Service: | 1889–1910 |
| Wars: | Spanish–American War |
| Designer: | Bureau of Ordnance |
| Design Date: | 1885 |
| Manufacturer: | U.S. Naval Gun Factory |
| Production Date: | 1885 |
| Number: | 2 |
| Variants: | Mark 1 Mod 0 and 1 |
| Weight: | 6190lb (without breech) |
| Length: | 159.97inches Mark 1 Mod 1 |
| Part Length: | 153.97inches bore (31 calibers) |
| Cartridge: | 50lb |
| Caliber: | 5inches |
| Rate: | 6 rounds per minute |
| Velocity: | 2300ft/s |
| Max Range: | 160000NaN0 at 30° elevation |
| Traverse: | −150° to +150° |
The 5"/31 caliber gun (spoken "five-inch-thirty-one-caliber") were used in the secondary batteries of the United States Navy's "New Navy" protected cruiser and later mounted in during the Spanish–American War.[1]
Mark 1, Nos. 1 and 2, were 31 calibers and two of the first steel tube guns that were built entirely in the United States. They were trunnioned guns, no liners and that fired bag ammunition. After the Spanish–American War was over they were modified to Mod 1 in 1901. A liner was inserted in the breech end and the trunnions were cut off. The Mod 1 consisted of tube, jacket, and 9 hoops. After these changes the gun was able to use the same ammunition as the later Mark 2 5-inch gun.[2]
| Ship | Gun Installed | Gun Mount | |
|---|---|---|---|
| Mark 1 Mod 0: 2 × 5"/30 caliber (removed April 1898) | Mark 1: 2 × single mounting with gravity return | ||
| Mark 1 Mod 0: 2 × 5"/30 caliber (installed July 1898) | Unknown |