View source for QF 4 inch naval gun Mk I – III

{{Infobox Weapon
|name= Ordnance QF 4-inch gun Mk I, II, III
|image=[[File:AIF troops with QF 4 inch Mk I-III gun 1914 AWM P00326.017.jpeg|300px]]
|caption=Australian troops with gun on a transport ship, circa. November 1914
|origin={{flagicon|United Kingdom}} [[United Kingdom of Great Britain and Ireland|United Kingdom]]
|type= [[Naval artillery|Naval gun]]<br>[[Coastal artillery|Coast defence gun]]
<!-- Type selection -->
|is_ranged=yes
|is_explosive=
|is_artillery=yes
|is_UK=yes
<!-- Service history -->
|service=1896 - 1920<ref>Remaining ships were all scrapped or decommissioned following WWI, by 1921 at latest</ref>
|used_by={{flagicon|United Kingdom}} [[United Kingdom of Great Britain and Ireland|United Kingdom]]
|wars= [[World War I]]
<!-- Production history -->
|designer= 
|design_date=1895
|manufacturer=
|production_date=
|number= 
|variants= 
<!-- General specifications -->
|weight={{convert|2912|lb|kg|sigfig=4}} barrel & breech
|length=
|part_length={{convert|160|in|m|sigfig=4}} bore (40 [[Caliber#Caliber_as_measurement_of_length|cal]]); {{convert|165.35|in|m|sigfig=4}} total 
|width=
|height=
|crew=
<!-- Ranged weapon specifications --> 
|cartridge=[[British ordnance terms#Separate QF|Separate-loading QF]] {{convert|25|lb|kg|sigfig=4}} [[British ordnance terms#Common Pointed|Common pointed]] or [[British ordnance terms#Common Lyddite|Lyddite]]
|caliber={{convert|4|in|mm|sing=on|sigfig=4}}
|action= 
|rate=
|velocity= {{convert|2300|ft/s|m/s}}<ref>2300 ft/s with {{convert|25|lb|abbr=on}} projectile in 1902, using {{convert|3|lb|9|oz|kg|abbr=on}} cordite Mk I size 15 propellant (Text Book of Gunnery 1902)</ref>
|range= 
|max_range= {{convert|9000|yd|m}}<ref>Text Book of Gunnery 1902, Table XII page 337</ref>
|sights= 
<!-- Artillery specifications -->
|breech=Single-motion screw
|recoil=
|carriage=
|elevation=
|traverse=
}}
The '''QF 4-inch gun Mks I, II, III''' were early British QF naval guns originating in 1895. They all had barrels of 40 [[Caliber#Caliber_as_measurement_of_length|calibres]] length.

==Naval service==
The gun was intended to be a more powerful alternative to the 3-inch [[QF 12 pounder 12 cwt naval gun|QF 12 pounder gun]].

It was mounted on the following ships :
*[[Pelorus class cruiser|''Pelorus''-class third class protected cruisers]] of 1896
*[[Condor class sloop|''Condor''-class sloops]] of 1898
*[[Cadmus class sloop|''Cadmus''-class sloops]] of 1900
*[[Topaze class cruiser|''Topaze''-class third-class cruisers]] launched in 1903
*[[Invincible class battlecruiser|''Invincible''-class battlecruisers]] of 1906

Its 25-pound shell proved insufficiently powerful to make it much of an improvement on the 12-pounder. From 1907 onwards it was succeeded in its class on new  warships by the [[BL 4 inch naval gun Mk VIII|BL 4 inch gun Mk VIII]], which fired a 31-pound shell.

==Coast Defence gun==
From 1906 a number of Mk III guns were transferred from the Royal Navy for use as coast defence guns around the United Kingdom, and remained until 1939.<ref>Hogg & Thurston 1972, page 96</ref>

In 1918 three guns were in service at Dover Garrison and eight at Forth Garrison.<ref>Farndale 1988, pages 398 - 404</ref>

==World War I land service==
On 20 September 1914 the British cruiser [[HMS Pegasus (1897)|HMS ''Pegasus'']] was sunk by [[SMS Königsberg (1905)|SMS ''Königsberg'']] in Zanzibar harbour. Her 8 QF 4-inch Mk III guns were recovered and used ashore in the [[East African Campaign (World War I)|East African campaign]]. Some were used as coast defence guns at Zanzibar and Mombasa. Two guns, and from 11 February 1916, three guns, were used by 10th Heavy Battery manned by the Royal Marines, mounted on improvised field carriages and towed by Packard lorries, supported by six [[:en:REO Motor Car Company|REO]] lorries carrying ammunition.<ref>Farndale 1988, page 316</ref>

==Surviving guns==
*A gun from HMS ''Pegasus'' used in the WWI land campaign stands outside [[Fort Jesus]] on Mombasa Island, Kenya, next to one of the 10.5-cm guns from [[SMS Königsberg (1905)|SMS ''Königsberg'']].<ref>Kevin Patience, [http://zanzibar.net/zanzibar/konigsberg Konigsberg: A German East African Raider]</ref>
*[[:File:Gun Dùn St Kilda.jpg|A gun installed in 1918]] on the island of [[Hirta]] in the [[St Kilda, Scotland|St Kilda]] archipelago, northwest Scotland

==See also==
*[[List of naval guns]]

==Notes==
{{Reflist}}

==References==
* [http://cgsc.cdmhost.com/u?/p4013coll11,230 Text Book of Gunnery, 1902. LONDON : PRINTED FOR HIS MAJESTY'S STATIONERY OFFICE, BY HARRISON AND SONS, ST. MARTIN'S LANE]
*General Sir Martin Farndale, [http://www.amazon.co.uk/dp/1870114051 History of the Royal Regiment of Artillery : Forgotten Fronts and the Home Base 1914-18. London:The Royal Artillery Institution, 1988]
* {{cite book |last= Hogg|first= I.V. and Thurston, L.F.|title= British Artillery Weapons & Ammunition 1914-1918|publisher=Ian Allan, London|year=1972|id=ISBN 7110 0381 5}}

==External links==
{{Commonscat|QF 4 inch naval gun Mk I - III}}
*Tony DiGiulian, [http://www.navweaps.com/Weapons/WNBR_4-40_mk3.htm British 4"/40 (10.2 cm) QF Marks I, II and III]

{{VictorianEraBritishNavalWeapons}}
{{GreatWarBritishNavalWeapons}}
{{GreatWarBritishWeapons}}


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[[Category:Naval guns of the United Kingdom]]
[[Category:100 mm artillery]]

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