Like other early Armstrong guns they were rifled on a polygroove system, firing a variety of lead coated projectiles.

[5] A 32 cwt variant having a horizontal sliding-wedge breech instead of the Armstrong screw with vertical vent-piece was introduced in 1864 as an attempt to address the perceived weaknesses of the screw-breech design.

These guns work very easily, are very true, and the drill is very simple.Following the bombardment of Alexandria in 1882, as part of the Anglo-Egyptian War, an armed train was employed.

A wooden siege carriage with wheels and attached limbers, enabled the guns to be drawn by teams of heavy horses.

Others were mounted on high "siege travelling carriages" for use as semi-mobile guns in forts, firing over parapets.

The war began when Great Britain, fearful of what it saw as growing Russian influence in Afghanistan, invaded the country from British India.

The first phase of the war ended in May 1879 with the Treaty of Gandamak, which permitted the Afghans to maintain internal sovereignty but forced them to cede control over their foreign policy to the British.