Editing Revolver cannon (section)

=== Modern ===
It was not until the mid-1940s that the first practical revolver cannon emerged.<ref name="Williams2002">{{Cite book |last=Williams |first=Anthony G. |title=Rapid Fire: The Development of Automatic Cannon, Heavy Machine-Guns and Their Ammunition for Armies, Navies and Air Forces |date=31 August 2000 |publisher=Airlife |isbn=978-1-84037-435-3 |location=West Sussex, United Kingdom |page=50 |language=en |oclc=1109578149}}</ref>

The archetypal revolver cannon is the [[Mauser MK 213]] from World War II, from which almost all current weapons are derived. However, various problems, such as only moderate improvements in rate of fire and muzzle velocity, coupled with excessive barrel wear, and the effects of the [[Combined Bomber Offensive|Allied bombing campaign]] against German industry,<ref name=":Hunter Weapons">{{Cite book|title=Volume 2, Part 3, Hunter Weapons, The 30mm ADEN Gun, Rocket Projectiles, Air To Air Missiles, Bombs, etc.|pages=2–6}}</ref> meant that at the end of the war only five prototypes (V1 to V5) of either 20 mm MG 213 or 30 mm MK 213 were finished.<ref name=":Hunter Weapons"/> In the immediate post-war era the unfinished weapon, and the engineers who worked on it, were seized by the [[Allies of World War II|Allies]] to continue development; Both the British and French worked on the 30&nbsp;mm versions of the MK 213, producing the [[ADEN cannon|ADEN]] and [[DEFA cannon|DEFA]], respectively. Switzerland produced the [[Oerlikon KCA]].  The American [[M39 cannon]] used the 20&nbsp;mm version, re-chambered for a slightly longer 102&nbsp;mm cartridge, intermediate between the MK 213's 82&nbsp;mm and [[Hispano-Suiza HS.404]]'s 110&nbsp;mm case lengths.  Several generations of the basic ADEN/DEFA weapons followed, remaining largely unchanged into the 1970s.<ref>{{Cite web |date=28 January 1955 |title=[untitled] |url=https://www.flightglobal.com/FlightPDFArchive/1955/1955%20-%200109.PDF |url-status=dead |archive-url=https://web.archive.org/web/20190812112345/https://www.flightglobal.com/FlightPDFArchive/1955/1955%20-%200109.PDF |archive-date=12 August 2019 |archive-format=PDF |access-date=11 February 2018 |page=109 |language=en |format=PDF |via=[[FlightGlobal]]}}</ref>

Around that time, a new generation of weapons developed, based on the proposed [[NATO]] [[25 mm caliber]] standard and the Mauser 27&nbsp;mm round.  A leading example is the [[Mauser BK-27]].  In the 1980s, the French developed the [[GIAT 30]], a newer generation power-driven revolver cannon.  The [[Rheinmetall RMK30]] modifies the GIAT system further, by venting the gas to the rear to eliminate recoil.

Larger experimental weapons have also been developed for anti-aircraft use, like the Anglo-Swiss twin barrel but single chamber 42&nbsp;mm [[Oerlikon RK 421]] given the code name "Red King" and the related single-barrel "Red Queen" - all of which were cancelled during development.<ref>{{Cite web |last=Williams |first=Anthony G. |title=The Red Queen and the Vigilante |url=http://www.quarry.nildram.co.uk/RED%20QUEEN.htm |url-status=dead |archive-url=https://web.archive.org/web/20110520121735/http://www.quarry.nildram.co.uk/RED%20QUEEN.htm |archive-date=20 May 2011 |access-date=28 May 2022 |website=www.quarry.nildram.co.uk/}}</ref>  The largest to see service is the [[Oerlikon Millennium 35 mm Naval Revolver Gun System|Rheinmetall Millennium 35 mm Naval Gun System]].

Soviet revolver cannon are less common than Western ones, especially on aircraft. A mechanism for a Soviet revolver-based machine gun was patented in 1944.<ref>{{Cite web |title=Pulemet s barabannym kamernym pitaniem A.I. Konovalova. 1944 g. |script-title=ru:Пулемет с барабанным камерным питанием А.И. Коновалова. 1944 г. |trans-title=Machine gun with drum chamber feed A.I. Konovalov. 1944 |url=http://rusarchives.ru/victory65/pages/04_14_1.htm |url-status=dead |archive-url=https://web.archive.org/web/20120828131643/http://www.rusarchives.ru/victory65/pages/04_14_1.htm |archive-date=28 August 2012 |access-date=26 July 2013 |publisher=[[Federal Archival Agency (Russia)|Federal Archival Agency]] |location=Moscow, Russia |language=ru}}</ref> The virtually unknown [[Rikhter R-23]] was fitted only to some [[Tu-22]] models, but later abandoned in favor of the two-barrel, [[Gast gun]] [[Gryazev-Shipunov GSh-23]] in the [[Tu-22M]]. The Rikhter R-23 does have the distinction of being fired from the space station [[Salyut 3]]. The Soviet navy has also adopted a revolver design, the NN-30, typically in a dual mount in the [[AK-230]] turret.