68-pounder gun

The 68-pounder cannon was an artillery piece designed and used by the British Armed Forces in the mid-19th century. The cannon was a smoothbore muzzle-loading gun manufactured in several weights, the most common being 95 long cwt (4,800 kg), and fired projectiles of 68 lb (31 kg). Colonel William Dundas designed the 112 cwt version in 1841 and it was cast the following year. The most common variant, weighing 95 cwt, dates from 1846. It entered service with the Royal Artillery and the Royal Navy and saw active service with both arms during the Crimean War. Over 2,000 were made and it gained a reputation as the finest smoothbore cannon ever made.

The gun was produced at a time when new rifled and breech loading guns were beginning to make their mark on artillery. At first the 68-pounder's reliability and power meant that it was retained even on new warships such as HMS Warrior, but eventually new rifled muzzle loaders made all smoothbore muzzle-loading guns obsolete. However, the large surplus stocks of 68-pounders were given new life when converted to take rifled projectiles; the cannon remained in service and was not declared obsolete until 1921.

68-pounder gun
Class Vehicle
Type Towed Artillery
Manufacturer Low Moor Ironworks
Production Period 1841 - 1861
Origin United Kingdom - UK (Great Britain)
Country Name Origin Year
United Kingdom - UK (Great Britain) 1846
Country Name Operational Year Retirement Year
United Kingdom - UK (Great Britain) 1846 1921 View
ManufacturerName Production From Production To Quantity
Low Moor Ironworks 1841 1861 2000 View

The cannon was designed in response to the need for heavier weaponry as armour on ships of the line improved. Colonel William Dundas, the government's Inspector of Artillery between 1839 and 1852, designed the cannon in 1846. It was cast by the Low Moor Iron Works in Bradford in 1847 and entered service soon after. Like numerous cannon before it, it was a cast iron smoothbore loaded from the muzzle. The cannon was relatively cheap to produce – the Royal Commission on the Defence of the United Kingdom estimated that each cannon cost approximately £167.(2010 : £12645). Over 2000 were cast before 1861 and its exceptional durability, range and accuracy earned it a reputation as the finest smoothbore cannon ever made.

The cannon was put to use both on land and at sea. It was fitted to numerous Royal Navy warships of different sizes such as HMS Queen, Odin, Victor Emmanuel, Sepoy and the Conqueror-class ships of the line. Several of these ships saw action during the Crimean War where the 68-pounder was used extensively during the Siege of Sevastopol. Along with 32-pounders and Lancaster guns they were taken from their ship mountings and dragged up to siege batteries by the Naval Brigade, from where they regularly bombarded Russian positions for the next year. The cannon was also fitted in large numbers to the Aetna-class ironclad floating batteries, although these had little impact on the war.

Most notably the 68-pounder was fitted to the Warrior-class ironclads Warrior and Black Prince. Originally it was intended to fit forty 68-pounders, primarily on one gun deck, but this specification changed during their building and they were finally equipped with twenty-six 68-pounders (13 on each side). Alongside these, the ships were equipped with new rifled breech loading Armstrong guns of two types; 7 inch and 40 pounders. Although the Armstrong guns represented a new direction in artillery, the breech loading mechanism meant that they were unable to withstand the explosion of a heavy cartridge. Smaller cartridge charges were therefore required and the gun's muzzle velocity suffered as a result. Ironically the Armstrong Guns were therefore incapable of penetrating the armour fitted to the Warrior-class ships, while the 68-pounder (with its high muzzle velocity) could. As late as 1867 it was planned to fit the new Plover-class gunvessels with 68-pounders, but they were instead completed with a RML 7 inch gun and a RML 64 pounder 64 cwt gun.

On land the 68-pounder was used extensively in British coastal defences constructed during the 1850s - notably at forts like Gomer and Elson defending Portsmouth, and Forts Victoria, Albert and Freshwater Redoubt defending the Needles Passage. The 1859 Royal Commission envisaged arming the numerous new forts they proposed with the 68-pounder cannon and costed for them accordingly. The introduction of the Armstrong gun initially led many to think that weapon would be used instead, but whilst the forts were being built, the Armstrong gun's weaknesses were exposed and the military reverted to using muzzle loaded weapons. However, the advantages of rifling and the Armstrong's wrought iron construction were retained, leading to a new design of artillery piece – rifled muzzle loaders.

Type Naval gun
Coast Defence gun
Place of origin United Kingdom
Service history
In service 1846–1921
Used by United Kingdom
Wars Crimean War
Production history
Designer William Dundas
Manufacturer Low Moor Iron Works
Unit cost £225
Produced 1841–1861
Number built In excess of 2,000
Specifications
Weight 88, 95 or 112 cwt
Barrel length 88 cwt: 9 feet 6 inches (2,896 mm)
95 cwt: 10 feet (3,048 mm)
112 cwt: 10 feet 10 inches (3.302 m)
Crew 9 – 18
Shell Solid Shot
Explosive Shell
Shell weight 68 pounds (30.84 kg)
Calibre 8.12 inches (20.62 cm)
Elevation 0 – 15 degrees
Muzzle velocity 1,579 feet per second (481 m/s)
Effective firing range Approximately 3,000 yards (2,700 m)
Maximum firing range 3,620 yards (3,310 m)

End notes