The MP 38 receiver was made of machined steel, but this was a time-consuming and expensive process. To save time and materials, and thus increase production, construction of the MP 40 receiver was simplified by using stamped steel and electro-spot welding as much as possible. The MP 38 also features longitudinal grooving on the receiver and bolt, as well as a circular opening on the magazine housing. These features were eliminated on the MP 40.
One feature found on most MP 38 and MP 40 submachine guns is an aluminum, steel, or Margolit (a variation of Bakelite) resting bar under the barrel. This was used to steady the weapon when firing over the side of open-top armored personnel carriers such as the Sd.Kfz. 251 half-track. A handguard, also made of Margolit, is located between the magazine housing and the Margolit pistol grip. The barrel lacked any form of insulation, which often resulted in burns on the supporting hand if it was incorrectly positioned. The MP 40 also has a forward-folding metal stock, the first for a submachine gun, resulting in a shorter overall weapon when folded. However, this stock design was at times insufficiently durable for hard combat use.
Although the MP 40 was generally reliable, a major weakness was its 32-round magazine. Unlike the double-column, staggered-feed magazine found on the Thompson M1921/1928 variants, the MP 40 uses a double-column, single-feed version. The single-feed insert resulted in increased friction against the remaining cartridges moving upwards towards the feed lips, occasionally resulting in feed failures; this problem was exacerbated by the presence of dirt or other debris. Another problem was that the magazine was also sometimes misused as a handhold. This could cause the weapon to malfunction when hand pressure on the magazine body caused the magazine lips to move out of the line of feed, since the magazine well did not keep the magazine firmly locked. German soldiers were trained to grasp either the handguard on the underside of the weapon or the magazine housing with the supporting hand to avoid feed malfunctions.
During and after the end of World War II, many MP 40s were captured or surrendered (upwards of 200,000) to the Allies and were then redistributed to the paramilitary and irregular forces of some developing countries. The Norwegian army withdrew the MP 38 from use in 1975 but used the MP 40 for some years more. In particular, the Territorials (Heimevernet) used it until about 1990, when it was replaced by the Heckler & Koch MP5.
In 1941, Hugo Schmeisser designed the MP 41, which was, in reality, an MP 40 upper receiver with a lower receiver of an MP 28/II submachine gun. It saw limited service, however, and was issued only to SS and police units in 1944. The MP 41 was also supplied to Germany's Axis ally Romania.
The MP 38 and MP 40 also directly influenced the design of later weapons, including the Spanish Star Z45, the Yugoslavian Zastava M56, and the semi-automatic German Selbstladebüchse BD 38 replica.
Details of the MP 40 have also been adopted in other submachine guns, which otherwise differ significantly from a technical point of view:
Archived at Ghostarchive and the Wayback Machine: "MP 40 - Role & Tactics". YouTube. 7 July 2020. https://ghostarchive.org/varchive/youtube/20211211/PXt3KWpcW2g
"MP40 Sub Machine Gun | ParaData". www.paradata.org.uk. Retrieved 27 March 2021. https://www.paradata.org.uk/article/mp40-sub-machine-gun
Rottman 2012, p. 9. - Rottman, Gordon L (2012). The AK-47: Kalashnikov-series Assault Rifles. Osprey Publishing. ISBN 978-1-84908-835-0.
de Quesada 2014, p. 13. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
"The Prototypes". mp40.nl. Retrieved 5 April 2019. https://www.mp40.nl/index.php?page=mp36-2
de Quesada 2014, p. 13. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
Peterson 2011, p. 314. - Peterson, Philip (2011). Standard Catalog of Military Firearms: The Collector's Price and Reference Guide. F+W Media, Inc. ISBN 978-1440228810.
Peterson 2011, p. 314. - Peterson, Philip (2011). Standard Catalog of Military Firearms: The Collector's Price and Reference Guide. F+W Media, Inc. ISBN 978-1440228810.
Bishop 2002, p. 259. - Bishop, Chris (2002). The Encyclopedia of Weapons of World War II. Sterling Publishing Company, Inc. ISBN 978-1586637620.
Bishop 2002, p. 259. - Bishop, Chris (2002). The Encyclopedia of Weapons of World War II. Sterling Publishing Company, Inc. ISBN 978-1586637620.
World Guns. - "Erma MP-38 and MP-40 submachine gun (Germany)". World Guns. Archived from the original on 4 June 2012. Retrieved 7 March 2015. https://web.archive.org/web/20120604034121/http://world.guns.ru/smg/de/mp3-mp40-e.html
de Quesada 2014, p. 17. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
de Quesada 2014, p. 17. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
de Quesada 2014, p. 17. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
Hobart 1975, pp. 95–98. - Hobart, Frank (1975). Pictorial History of the Sub-machine Gun. Scribner Publishing. ISBN 978-0684141862.
Hobart 1975, pp. 95–98. - Hobart, Frank (1975). Pictorial History of the Sub-machine Gun. Scribner Publishing. ISBN 978-0684141862.
Hogg & Weeks 1977, p. 90. - Hogg, Ian; Weeks, John, eds. (1977). Military Small Arms of the 20th Century. Arms & Armour Press. ISBN 0-85368-301-8.
Hogg & Weeks 1977, p. 90. - Hogg, Ian; Weeks, John, eds. (1977). Military Small Arms of the 20th Century. Arms & Armour Press. ISBN 0-85368-301-8.
Hogg & Weeks 1977, p. 33. - Hogg, Ian; Weeks, John, eds. (1977). Military Small Arms of the 20th Century. Arms & Armour Press. ISBN 0-85368-301-8.
Hogg & Weeks 1977, p. 33. - Hogg, Ian; Weeks, John, eds. (1977). Military Small Arms of the 20th Century. Arms & Armour Press. ISBN 0-85368-301-8.
Hogg & Weeks 1977, p. 33. - Hogg, Ian; Weeks, John, eds. (1977). Military Small Arms of the 20th Century. Arms & Armour Press. ISBN 0-85368-301-8.
Dunlap 1966, pp. 80–81. - Dunlap, Roy (1966). Ordnance Went Up Front. R & R Books. ISBN 978-1884849091.
Dunlap 1966, pp. 80–81. - Dunlap, Roy (1966). Ordnance Went Up Front. R & R Books. ISBN 978-1884849091.
Dunlap 1966, pp. 80–81. - Dunlap, Roy (1966). Ordnance Went Up Front. R & R Books. ISBN 978-1884849091.
Neil 2015, p. 65. - Neil, Grant (2015). Mauser Military Rifles. Osprey Publishing. ISBN 978-1472805942.
Priestley & Cavatore 2014, pp. 105–108. - Priestley, Rick; Cavatore, Alessio, eds. (2014). Bolt Action: World War II Wargames Rules. Osprey Publishing. ISBN 978-1782009702.
Priestley & Cavatore 2014, pp. 105–108. - Priestley, Rick; Cavatore, Alessio, eds. (2014). Bolt Action: World War II Wargames Rules. Osprey Publishing. ISBN 978-1782009702.
Neil 2015, p. 65. - Neil, Grant (2015). Mauser Military Rifles. Osprey Publishing. ISBN 978-1472805942.
Willbanks 2004, p. 82. - Willbanks, James (2004). Machine Guns: An Illustrated History of Their Impact. ABC-CLIO. ISBN 978-1851094806.
Ingram 2001, p. 75. - Ingram, Mike (2001). The MP40 Submachine Gun. Zenith Imprint. ISBN 0-7603-1014-9.
World Guns. - "Erma MP-38 and MP-40 submachine gun (Germany)". World Guns. Archived from the original on 4 June 2012. Retrieved 7 March 2015. https://web.archive.org/web/20120604034121/http://world.guns.ru/smg/de/mp3-mp40-e.html
The WW2 Double-Magazine MP40/I https://www.forgottenweapons.com/the-ww2-double-magazine-mp40-i/
Axworthy 1991, p. 42. - Axworthy, Mark (1991). The Romanian Army of World War II. Osprey Publishing. ISBN 978-1855321694.
"MP41". Imperial War Museums. Retrieved 5 July 2020. https://www.iwm.org.uk/collections/item/object/30029383
"MP.41 Schmeisser". Modern Firearms. 27 October 2010. Retrieved 5 July 2020. https://modernfirearms.net/en/submachine-guns/germany-submachine-guns/mp-41-schmeisser-eng/
Sakaida, Henry (20 May 2003). Hook, Christa (ed.). Heroines of the Soviet Union 1941-45. Bloomsbury Publishing. p. 59. ISBN 1841765988. 1841765988
Cornish, Nik (20 June 2014). Karachtchouk, Andrei (ed.). Soviet Partisan 1941-45. Bloomsbury Publishing. p. 29. ISBN 9781472801456. 9781472801456
Weckstein, Leon (2011). 200,000 Heroes: Italian Partisans and the American OSS in WWII. Hellgate Press. p. 233. ISBN 9781555716981. 9781555716981
Noir, War. "#Russia #Ukraine 🇷🇺🇺🇦: A new photo posted by a combatant of #DPR/#DNR Forces in #Donbas/#Donbass. The combatant seems to be carrying a fairly noteable [sic] "MP 40" ('Maschinenpistole 40') submachine gun, claimed to be seized from #Ukrainian Troops". x.com. War Noir. Retrieved 12 February 2025. https://x.com/war_noir/status/1550544494348697600
Campbell, David (2016). Israeli Soldier vs Syrian Soldier: Golan Heights 1967–73. Combat. illustrated by Johnny Shumate. Osprey Publishing. p. 10. ISBN 9781472813305. 9781472813305
B, Eric (6 April 2017). "MP40 sub-machine gun in Syria". thefirearmblog.com. Retrieved 12 February 2025. https://www.thefirearmblog.com/blog/2017/04/06/mp40-sub-machine-gun-syria/
Noir, War. "#Russia #Ukraine 🇷🇺🇺🇦: #Russian Forces have released a photo of the weapons allegedly seized from #Ukrainian Combatants in #Gostomel (#Hostomel), #Kyiv/#Kiev". x.com. War Noir. Retrieved 12 February 2025. https://x.com/war_noir/status/1505903903275200517
Windrow, Martin (1997). The Algerian War, 1954-62. Men-at Arms 312. London: Osprey Publishing. pp. 10&37. ISBN 978-1-85532-658-3. 978-1-85532-658-3
de Quesada 2014, p. 66. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
de Quesada 2014, p. 64. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
de Quesada 2014, p. 28. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
de Quesada 2014, p. 66. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
Brnardic, Vladimir (17 November 2016). Aralica, Višeslav (ed.). World War II Croatian Legionaries: Croatian Troops Under Axis Command 1941—45. Bloomsbury Publishing. p. 17. ISBN 978-1-4728-1767-9. 978-1-4728-1767-9
de Quesada 2014, p. 66. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
"FINNISH ARMY 1918 - 1945: MACHINEPISTOLS PART 2". www.jaegerplatoon.net. Retrieved 14 November 2022. https://www.jaegerplatoon.net/MACHINEPISTOLS2.htm
de Quesada 2014, p. 66. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
Windrow, Martin (15 November 1998). The French Indochina War 1946–54. Men-at-Arms 322. Osprey Publishing. p. 12. ISBN 9781855327894. 9781855327894
"L'armement français en A.F.N." Gazette des Armes (in French). No. 220. March 1992. pp. 12–16. Archived from the original on 8 October 2018. Retrieved 8 October 2018. https://web.archive.org/web/20181008174853/http://fr.1001mags.com/parution/gazette-des-armes/numero-220-mars-1992/page-12-13-texte-integral
de Quesada 2014, p. 66. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
McNab, Chris (2002). 20th Century Military Uniforms (2nd ed.). Kent: Grange Books. p. 124. ISBN 1-84013-476-3. 1-84013-476-3
Perutka, Lukáš (September 2014). Checoslovaquia, Guatemala y México en el Período de la Revolución Guatemalteca: Ibero-Americana Pragensia - Supplementum 32/2013 (in Spanish). Karolinum Press. p. 110. ISBN 978-80-246-2429-7. 978-80-246-2429-7
Montes, Julio A. (4 December 2015). "Police Small Arms Arsenals in the Northern Central American Triangle". Small Arms Defense Journal. Vol. 7, no. 5. http://www.sadefensejournal.com/wp/?p=3259
Tibor, Rada (2001). "Német gyalogsági fegyverek magyar kézben" [German infantry weapons in Hungarian hands]. A Magyar Királyi Honvéd Ludovika Akadémia és a Testvérintézetek Összefoglalt Története (1830-1945) (in Hungarian). Vol. II. Budapest: Gálos Nyomdász Kft. p. 1114. ISBN 963-85764-3-X. 963-85764-3-X
de Quesada 2014, p. 77. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
Katz 1988, p. 9. - Katz, Samuel (1988). Israeli Elite Units Since 1948. Osprey Publishing. ISBN 0-85045-8374.
"Silah Report Podcast V33: Iranian Submachine Guns (1941-1979)". 21 June 2021. https://silahreport.com/2021/06/21/iranian-submachine-guns-1941-1979/
Gianluigi, Usai; Riccio, Ralph (28 January 2017). Italian partisan weapons in WWII. Schiffer Military History. pp. 184–185. ISBN 978-0764352102. 978-0764352102
de Quesada 2014, p. 69. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
de Quesada 2014, p. 20. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
"Kiprah Tempur Pasukan Belanda" [Dutch Troops Combat History]. Angkasa Edisi Koleksi No. 82: Kisah Heroik Pertempuran Laut Trikora (in Indonesian). Jakarta: Kompas Gramedia Group. February 2013. p. 90. /wiki/Kompas_Gramedia_Group
de Quesada 2014, p. 68. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
de Quesada 2014, p. 56. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
de Quesada 2014, p. 23. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
Sakaida, Henry (20 May 2003). Hook, Christa (ed.). Heroines of the Soviet Union 1941-45. Bloomsbury Publishing. p. 59. ISBN 1841765988. 1841765988
Cornish, Nik (20 June 2014). Karachtchouk, Andrei (ed.). Soviet Partisan 1941-45. Bloomsbury Publishing. p. 29. ISBN 9781472801456. 9781472801456
Williams, Anthony G.; Popenker, Maxim (15 January 2012). Sub-Machine Gun: The Development of Sub-Machine Guns and their Ammunition from World War 1 to the Present Day. Crowood Press UK. p. 15. ISBN 978-1847972934. 978-1847972934
Ezell, Edward Clinton (1988). Personal firepower. The Illustrated history of the Vietnam War 15. Bantam Books. pp. 42–44. ISBN 9780553345490. OCLC 1036801376. 9780553345490
de Quesada 2014, p. 64. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
Rottman, Gordon L. (25 July 2002). Green Beret in Vietnam 1957–73. Warrior 28. Osprey Publishing. p. 41. ISBN 9781855325685. 9781855325685
Ezell, Edward Clinton (1988). Personal firepower. The Illustrated history of the Vietnam War 15. Bantam Books. pp. 42–44. ISBN 9780553345490. OCLC 1036801376. 9780553345490
de Quesada 2014, p. 66. - de Quesada, Alejandro (2014). MP 38 and MP 40 Submachine Guns. Osprey Publishing. ISBN 978-1780963884.
Abbott, Peter; Botham, Philip (15 June 1986). Modern African Wars (1): Rhodesia 1965–80. Men-at-Arms 183. Osprey Publishing. p. 10. ISBN 9780850457285. 9780850457285
"Chapter XVIII: The Occupation Troops". history.army.mil. Retrieved 5 January 2018. https://history.army.mil/books/wwii/Occ-GY/ch18.htm
"Lot 1566: German - MP 40". www.rockislandauction.com. Retrieved 19 March 2021. https://www.rockislandauction.com/detail/71/1566/german-mp-40
Iannamico, Frank (1 December 2017). "MP 40 Road Test". Small Arms Review. Retrieved 29 July 2022. http://www.smallarmsreview.com/display.article.cfm?idarticles=3953
"Submachine Guns". Machine Gun Price Guide. April 2022. Retrieved 29 July 2022. http://machinegunpriceguide.com/html/subguns.html
Grant, Jim (19 January 2014). "ATI's GSG MP40, the quintessential bad-guy gun". Guns.com. Retrieved 5 January 2018. http://www.guns.com/2014/01/19/mp40-22lr/
Johnson, Steve (24 February 2016). "BREAKING NEWS: ATF Approve ATI MP40 9mm Pistol (Pistol Version of German WWII MP40 Submachine Gun) - The Firearm Blog". The Firearm Blog. Retrieved 5 January 2018. http://www.thefirearmblog.com/blog/2016/02/24/breaking-news/