RML 8-inch 9-ton gun

Naval gun

RML 8-inch 9-ton gun
Gundeck of HMS Northumberland
Type	Naval gun Coast defence gun
Place of origin	United Kingdom
Service history
In service	1866–190?
Used by	Royal Navy
Production history
Manufacturer	Royal Arsenal
Unit cost	£568^[1]
Variants	Mk I – Mk III
Specifications
Mass	9 long tons (9.1 t)
Barrel length	118 inches (3.0 m) bore + chamber^[2]

Shell	174 pounds 12 ounces (79.3 kg)^[3]
Calibre	8-inch (203.2 mm)
Muzzle velocity	1,420 feet per second (430 m/s)^[4]

The British RML 8-inch 9-ton guns Mark I – Mark III^[5] were medium rifled muzzle-loading guns used to arm smaller ironclad warships and coast defence batteries in the later 19th century.

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 in (810 cm)) 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.^[6]

Surviving examples

Notes and references

^ Unit cost of £567 12 shillings 10 pence is quoted in "The British Navy" Volume II, 1882, by Sir Thomas Brassey. Page 38
^ Text Book of Gunnery 1887 Table XVI page 313
^ 174 lb 12 oz projectile. Text Book of Gunnery 1887 Table XVI page 313
^ 1,420 feet/second firing 174-pound 12-oz projectile . Text Book of Gunnery 1887 Table XVI page 313
^ Mark I – Mark III = Mark 1 through to Mark 3. Britain used Roman numerals to denote Marks (models) of ordnance until after World War II. Hence this article describes the three models of RML 8-inch guns.
^ Gas-checks in British RML heavy guns

Bibliography

Text Book of Gunnery, 1887. LONDON : PRINTED FOR HIS MAJESTY'S STATIONERY OFFICE, BY HARRISON AND SONS, ST. MARTIN'S LANE Archived 2012-12-04 at archive.today
Sir Thomas Brassey, The British Navy, Volume II. London: Longmans, Green and Co. 1882

External links

Wikimedia Commons has media related to RML 8 inch 9 ton gun.

British Empire naval weapons of the Victorian era

Smoothbore muzzle-loading cannons

Smoothbore muzzle-loading shell guns

8-inch
10-inch 86 cwt

Mortars

10-inch Blomefield
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24-pounder Millar

Rifled breechloaders (Armstrong)

Rifled muzzle-loaders (Lancaster)

68-pounder Lancaster gun

Rifled muzzle-loaders (converted)

RML 64-pounder 71 cwt

Rifled muzzle-loaders (Woolwich)

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Quick-firing guns

Light weapons

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Whitehead torpedo

British Empire small arms & ordnance of the Victorian era

Sidearms

Muskets and rifles

Artillery

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Mountain artillery	RML 7-pounder Mountain Gun RML 2.5-inch Mountain Gun
Howitzers, medium, and heavy artillery	RML 6.3-inch howitzer RML 6.6-inch howitzer BL 5-inch howitzer BL 5.4-inch howitzer
Siege & garrison artillery	4.1-inch 'Long Cecil' SBBL 32-pounder SBML 24-pounder SBML 8-inch 65 cwt RBL 40-pounder RBL 7-inch RML 25-pounder 18 cwt RML 40-pounder gun RML 64-pounder 64 cwt gun RML 64-pounder 58 cwt RML 64-pounder 71 cwt gun RML 80-pounder RML 6.6-inch gun RML 8-inch howitzer BL 5-inch gun Mk I – V BL 6-inch 30 cwt howitzer BL 9.45-inch howitzer
Coastal artillery	QF 3-pounder Nordenfelt QF 4.7-inch BL 6-inch Mk III, IV, VI BL 6-inch Mk V RBL 7-inch RML 7-inch RML 8-inch BL 8-inch Mk VII RML 9-inch BL 9.2-inch Mk IV & VI BL 10-inch Mk I BL 12-inch Mk I, VI, VII RML 12.5-inch RML 16-inch RML 17.72-inch