| 70-pounder Whitworth gun | |
|---|---|
 Gun from Princess Royal, in Willard Park at the Washington Navy Yard. Notice the hexagonal bore. | |
| Type | Naval gun |
| Place of origin | United Kingdom |
| Service history | |
| In service | 1863– |
| Used by | Confederate States, United States, Brazil |
| Wars | American Civil War, Paraguayan War |
| Production history | |
| Designer | Joseph Whitworth |
| Manufacturer | Joseph Whitworth |
| Unit cost | £3500 |
| Produced | 1863?– |
| Specifications | |
| Mass | 8,582 pounds (3,892.7 kg) |
| Length | 118 inches (2.997 m) |
| Shell | Solid shot Explosive shell |
| Shell weight | 81 pounds (36.7 kg) |
| Calibre | 5.5-inch (140 mm) |
| Maximum firing range | 5,540 yards (5,070 m) |
| Filling | Black powder |
| Filling weight | 3 pounds 12 ounces (1.7 kg)[1] |
The 70-pounder Whitworth naval gun was designed by Joseph Whitworth during the 1860s. It was a rifled muzzle loader and used his hexagonal, rifled-bore design.
- ^ Holley, p. 34