| 120-pounder Whitworth gun | |
| Origin: | United Kingdom |
| Type: | Naval gun |
| Is Ranged: | yes |
| Is Explosive: | y |
| Is Artillery: | yes |
| Is Uk: | yes |
| Service: | 1865– |
| Used By: | Brazil |
| Manufacturer: | Joseph Whitworth |
| Production Date: | 1865?– |
| Weight: | 16660lb |
| Length: | 144inches |
| Cartridge: | Solid shot Explosive shell |
| Cartridge Weight: | 151lb |
| Caliber: | 7sing=onNaNsing=on |
| Max Range: | about 5540yd |
| Filling Weight: | 5lb[1] |
The 120-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, the principle of which is described in the article on the 70-pounder Whitworth naval gun.
A number of 120-pounders were bought by the Imperial Brazilian Navy and used to arm some of its ironclads during the Paraguayan War in the late 1860s.[2]