Place of origin United Kingdom Used by Royal Navy Unit cost £568 | In service 1866 - 190? Manufacturer Royal Arsenal | |
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Type Naval gun
Coast defence gun | ||
The British RML 8 inch 9 ton guns Mark I - Mark III were medium rifled muzzle-loading guns used to arm smaller ironclad warships and coast defence batteries in the later 19th century.
Contents
Design
In common with other Royal Ordnance RML designs of the 1860s, Mark I used the strong but expensive Armstrong system of a steel tube surrounded by a complex system of multiple wrought-iron coils, which was progressively simplified in Marks II and III to reduce costs : Mark III consisted only of A tube, B tube, breech coil and cascabel screw.
Rifling was of the "Woolwich" pattern of a small number of broad shallow grooves : 4 grooves with twist increasing from 0 to 1 turn in 40 calibres (i.e. in 320 inches) at the muzzle.
Ammunition
The ammunition was mainly studded, with the studs engaging in the Woolwich rifling grooves. However, a studless pointed common shell with automatic gas-check also became available later in the gun's life.