100-ton gun
| Armstrong 100-ton gun | |
|---|---|
"Rockbuster" at Napier of Magdala Battery, Gibraltar | |
| Type | Naval gun Coast defence gun |
| Place of origin | United Kingdom |
| Service history | |
| In service | 1877-1906 |
| Production history | |
| Designer | Elswick Ordnance Company |
| Unit cost | £16,000 (approximately £1.64 million in 2025 GBP) |
| No. built | 15 |
| Specifications | |
| Mass | 103 tons |
| Barrel length | bore: 363.0 inches (9.22 m) (20.5 calibres) |
| Shell | HE, AP, Shrapnel, 2,000 pounds (910 kg) |
| Calibre | 450-millimetre (17.72 in) |
| Recoil | 1.75 m (5 ft 9 in) |
| Elevation | 10° 30' |
| Traverse | 150° |
| Muzzle velocity | 1,548 feet per second (472 m/s) (Firing a 1,968 lb projectile with 450 lb Prism powder propellant) |
| Maximum firing range | 6,600 yards (6,000 m) |
The 100-ton gun (also known as the Armstrong 100-ton gun) was a British coastal defense gun and is the world's largest black powder cannon. It was a 17.72-inch (450 mm) rifled muzzle-loading (RML) gun made by Elswick Ordnance Company, the armaments division of the British manufacturing company Armstrong Whitworth, owned by William Armstrong. The 15 guns Armstrong made were used to arm two Italian battleships and, to counter these, British fortifications at Malta and Gibraltar.