View source for .380 ACP

{{Short description|Pistol cartridge designed by John Moses Browning}}
{{distinguish|.38 ACP}}
{{Infobox firearm cartridge
|name = .380 ACP
|image = 380 ACP - FMJ - SB - 2.jpg
|caption = A .380 ACP pistol cartridge by [[Sellier & Bellot]]
|origin = United States
|type = [[Pistol]]
<!-- Service history -->
|service = 
|used_by = 
|wars = 
<!-- Production history -->
|designer = [[John Browning]]
|manufacturer = [[Colt's Manufacturing Company]]
|design_date = 1908
|production_date = 1908–present
|number = 
|variants = 
<!-- Specifications -->
|is_SI_specs = 
|parent = 
|case_type = Rimless, straight
|bullet = .355
|land = .348
|neck = .373
|shoulder = 
|base = .374
|rim_dia = .374
|rim_thick = .045
|case_length = .680
|length = .984
|case_capacity = 11.8 grains h20
|primer = Small pistol
|max_pressure=21500
<!-- Ballistic performance -->
|is_SI_ballistics = 
|bw1 = 90
|btype1 = Buffalo JHP
|vel1 = 1025
|en1 = 210
|bw2 = 95
|btype2 = Federal FMJ
|vel2 = 980
|en2 = 203
|bw3 = 45
|btype3 = RBCD TFSP
|vel3 = 1835
|en3 = 337
|bw4 = 100
|btype4 = Buffalo +P HC-FN
|vel4 = 1160
|en4 = 299
|bw5 = 85
|btype5 = Norma MHP
|vel5 = 1280
|en5 = 309
|test_barrel_length = {{convert|3.75|in|mm|1}}
|balsrc = {{ubl|Federal Cartridge<ref>{{cite web |url=http://www.federalcartridge.com/ballistics/ |title=Federal Cartridge Ballistics |website=Federal Cartridge| access-date=2007-09-25 | archive-url=https://web.archive.org/web/20070927040132/http://www.federalcartridge.com/ballistics/| archive-date=27 September 2007<!--Added by DASHBot-->}}</ref>|
Buffalo Bore Ammunition<ref>{{cite web |title=Buffalo Bore .380 ACP +P 100gr. Hard Cast F.N. |url=https://www.buffalobore.com/index.php?l=product_detail&p=127 |website=Buffalo Bore Ammunition |access-date=25 June 2021}}</ref>|
RBCD Performance Plus Ammunition<ref>{{cite web |title=380 Auto RBCD Performance Plus 45gr. Total Fragmenting Soft Point Ammo |url=https://www.ammunitiontogo.com/product_info.php/pName/20rds-380-auto-rbcd-performance-plus-45gr-total-fragmenting-soft-point-ammo |website=RBCD Performance Plus Ammunition |access-date=7 July 2021}}</ref>|
Norma Ammunition<ref>{{cite web |title=Norma .380 Auto MHP 85 gr |url=https://www.norma-ammunition.com/en-us/products/dedicated-home-defence/pistol-and-revolver/norma-mhp/norma-380-auto-mhp-85-gr---610040020 |website=Norma Ammunition |access-date=8 July 2021}}</ref>}}
}}

The '''.380 ACP''' ([[Automatic Colt Pistol]]), also known as '''.380 Auto''', '''.380 Automatic''', or '''9×17mm''', is a [[Rim (firearms)|rimless]], straight-walled [[pistol]] [[Cartridge (firearms)|cartridge]] that was developed by [[firearm]]s designer [[John Browning|John Moses Browning]].  The cartridge [[Headspace (firearms)|headspaces]] on the mouth of the case.<ref name="wilson">Wilson, R. K. ''Textbook of Automatic Pistols'', p. 241. Plantersville, SC: Small Arms Technical Publishing Company, 1943.</ref>  It was introduced in 1908 by [[Colt's Manufacturing Company|Colt]], for use in its new [[Colt Model 1903 Pocket Hammerless]] [[Semi-automatic pistol|semi-automatic]], and has been a popular [[self-defense]] cartridge ever since, seeing wide use in numerous handguns (typically smaller weapons). Other names for .380 ACP include '''9mm Browning''', '''9mm Corto''', '''9mm Kurz''', '''9mm Short''', and '''9mm Browning Court''' (which is the [[Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives|C.I.P.]] designation). It should not be confused with [[.38 ACP]]. The .380 ACP does not strictly conform to cartridge naming conventions, named after the diameter of the [[bullet]], as the actual bullet diameter of the .380 ACP is .355 inches.

==Design==
The .380 ACP cartridge was derived from Browning's earlier [[.38 ACP]] design, which was only marginally more powerful. The .380 ACP was designed to be truly [[Rim (firearms)#Rimless|rimless]], and [[Headspace (firearms)|headspaces]] on the case mouth instead of the rim for better accuracy. These relatively low-powered designs were intended for [[Blowback (firearms)|blowback]] pistols which lacked a [[Gun barrel|barrel]] [[Recoil operation|locking mechanism]], which is often required for any handgun firing a round more powerful than a .380 ACP. Using blowback operation, the design can be simplified, and lowered in cost; a locking mechanism is unnecessary, since the mass of the slide and strength of the recoil spring are enough to absorb the recoil energy of the round, due to the round's relatively low [[bolt thrust]]. Blowback operation also permits the barrel to be permanently fixed to the frame, which promotes accuracy, unlike a traditional [[Recoil operation|short recoil-operation]] pistol, which requires a tilting barrel to unlock the slide and barrel assembly when cycling. A drawback of the blowback system is that it requires a certain amount of slide mass to counter the recoil of the round used. The higher the power of the round, the heavier the slide assembly has to be in order for its inertia to safely absorb the recoil, meaning that a typical blowback pistol in a given caliber will be heavier than an equivalent recoil-operated weapon. Blowback weapons can be made in calibers larger than .380 ACP, but the required weight of the slide and strength of the spring makes this an unpopular option.

Although the low power of the .380 ACP does not require a locking mechanism, there have been a number of locked-breech pistols chambered in .380 ACP, such as the [[Remington Model 51]], [[Kel-Tec P-3AT|Kel-Tec P3AT]] and [[Glock#Glock 42|Glock 42]]; all three being designed to be lighter than blowback-operated .380 ACP weapons. There have also been some relatively diminutive (blowback-operated) [[submachine gun]]s, such as the Ingram [[MAC-11]]<ref>{{cite web | url=http://world.guns.ru/smg/smg22-e.htm | title=Ingram MAC Model 10 / M10 and Model 11 / M11 submachine guns (USA) | access-date=2007-09-25 | archive-url=https://web.archive.org/web/20070929124518/http://www.world.guns.ru/smg/smg22-e.htm | archive-date=29 September 2007<!-- Added by DASHBot -->}}</ref><ref name="Iannamico">{{cite journal | last=Iannamico | first=Ian | title=Manufacturing History of Ingram-MAC Type Firearms | journal=Small Arms Review | publisher=Chipotle Publishing, LLC | volume=20 | issue=1 | pages=102}}</ref> and the [[CZ 82#Caliber|Czech CZ 83]].<ref>{{cite book | last=Jones | first=Richard | title=Jane's Infantry Weapons 2009-2010 | publisher=Jane's Information Group | year=2009 | isbn=978-0-7106-2869-5 | page=107}}</ref>

==Users==
The .380 ACP has experienced widespread usage since its introduction in the United States (1908) and in Europe (1912). It was later adopted by the armies of at least five European nations as their standard pistol cartridge before [[World War II]]; Czechoslovakia [[ČZ vz. 38|(Vz.38)]], Hungary [[FÉG 37M Pistol|(FEMARU 37M)]], and Italy, all of whom used domestic designs, as well as The Netherlands and Yugoslavia, both of whom adopted the [[FN Model 1910|FN Model 1922]]. It was also used extensively by Germany, who captured or purchased hundreds of thousands of pistols in this caliber during World War II. Popular German built commercial models, such as the [[Walther PP#PPK|Walther PPK]] were very popular with German officers. The Italian Army used the [[Beretta M1934]], but the [[Italian Air Force]] and [[Italian Navy|Navy]] stuck with the [[.32 ACP|7.65mm/.32 ACP]] when they adopted the [[Beretta M1935]].

While the .380 ACP was considered to be a moderately powerful service pistol round before World War II when compared to the .32 ACP pistols it replaced, few nations retained it as a military service cartridge for very long after the war (it was eventually replaced by the more powerful [[9×19mm Parabellum]] after NATO standardization in the 1960s). It was widely used by police forces in Europe until the 1970s, when more powerful 9×19mm handguns began to replace it in this market. It does find some use as a backup gun due to the generally small and easily concealable size of the weapons that chambered it (very few "mini pistols" are made in calibers larger than .380 ACP, and those few are recent developments), and is popular on the civilian market as a personal defense round. The .380 ACP round is suitable for self-defense situations as a choice for concealed carry pistols. It was the round used in [[Defense Distributed]]'s "Wiki Weapon" project to [[Liberator (gun)|successfully 3D print a firearm]].

==Performance==
[[File:380 Auto vs 9mm Luger.jpg|thumb|The .380 ACP compared to a [[9×19mm Parabellum|9mm Luger]] cartridge.]]
The .380 ACP is compact and light, but has a shorter range and less [[stopping power]] than other modern pistol cartridges, depending on the load of the cartridge and manufacturer.<ref>{{cite web |url=http://www.stevespages.com/page8f380acp.html |title=.380ACP Terminal Ballistics |access-date=2007-09-25| archive-url=https://archive.today/20071016225924/http://stevespages.com/page8f380acp.html| archive-date=16 October 2007<!--Added by DASHBot-->}}</ref> .380 ACP remains a popular self-defense cartridge for shooters who want a lightweight or smaller pistol with manageable recoil. It is slightly less powerful than a standard-pressure [[.38 Special]], but also uses 9&nbsp;mm (.355 in) diameter bullets.  The standard bullet weights are generally {{convert|80|gr|abbr=on}}, {{convert|85|gr|abbr=on}}, {{convert|90|gr|abbr=on}}, {{convert|95|gr|abbr=on}}, {{convert|100|gr|abbr=on}}, {{convert|115|gr|abbr=on}}, and {{convert|120|gr|abbr=on}}.<ref>{{cite book|page=321|title=Lyman 48 Edition Reloading Handbook|year=2002|editor=Thomas J. Griffin}}</ref><ref>{{cite web|url=https://www.shootingillustrated.com/articles/2012/4/10/380-acp-drt-85-grain/|title=.380 ACP DRT 85-grain|access-date=October 28, 2018|date=April 10, 2012|author=Richard Mann}}</ref>

The wounding potential of a bullet is often characterized in terms of its expanded diameter, penetration depth, and energy. Bullet energies for .380 ACP loads vary from {{convert|190|to|294|ftlbf|J|abbr=on}}.<ref>{{cite web|url=http://www.buffalobore.com/index.php?l=product_detail&p=127%7Caccess-date=2018-07-29|title=380 Auto +P Pistol & Handgun Ammunition|website=www.buffalobore.com|access-date=2019-01-02|archive-date=2019-01-02|archive-url=https://web.archive.org/web/20190102193432/http://www.buffalobore.com/index.php?l=product_detail&p=127%7Caccess-date=2018-07-29|url-status=dead}}</ref> The table below shows common performance parameters for several .380 ACP loads. Bullet weights ranging from {{convert|85|to|95|gr|1|abbr=on}} are the most common. Penetration depths from {{convert|6.5|to|17|in|cm|1}} are available for various applications and risk assessments.

{| class="wikitable"
|-
! Manufacturer
! Load
! Mass 
! Velocity 
! Energy 
! Expansion<ref name="MS1996">{{citation| first1=Evan P. |last1=Marshall |first2=Edwin J. |last2=Sanow |publisher=Paladin Press |work=Street Stoppers| year=1996 | title=Appendix A| isbn=978-0-87364-872-1}}</ref>
! Penetration<ref name="MS1996" />
! PC<ref name="MS1996" />
! TSC<ref name="MS1996" />
|-
| Atomic Ammo
| Bonded [[Jacketed hollow point|JHP]]
| {{convert|90|gr|1|abbr=on}}
| 1,100&nbsp;ft/s
(335&nbsp;m/s)
| {{convert|241|ftlbf|abbr=on}}
| {{convert|0.64|in|1|abbr=on}}
| {{convert|12.0|in|1|abbr=on}}
| N/A
| N/A 
|-
| [[Cor-Bon]]
| JHP
| {{convert|90|gr|1|abbr=on}}
| {{convert|1050|ft/s|abbr=on}}
|220&nbsp;ft⋅lbf

(298 J)
| {{convert|0.58|in|1|abbr=on}}
| {{convert|9.0|in|1|abbr=on}}
| {{convert|2.38|cuin|1|abbr=on}}
| {{convert|15.7|cuin|1|abbr=on}}
|-
| [[Federal Premium Ammunition|Federal]]
| HydraShok JHP
| {{convert|90|gr|1|abbr=on}} 
| 1,000&nbsp;ft/s
(305&nbsp;m/s)
| 200&nbsp;ft⋅lbf
(271 J)
| {{convert|0.58|in|1|abbr=on}}
| {{convert|10.5|in|1|abbr=on}}
| {{convert|2.77|cuin|1|abbr=on}}
| {{convert|21.0|cuin|1|abbr=on}}
|-
| [[Winchester Ammunition|Winchester]]
| Silvertip JHP
| {{convert|85|gr|1|abbr=on}}
|1,000&nbsp;ft/s

(305&nbsp;m/s)
| {{convert|189|ftlbf|abbr=on}}
| {{convert|0.63|in|1|abbr=on}}
| {{convert|6.5|in|1|abbr=on}}
| {{convert|2.03|cuin|1|abbr=on}}
| {{convert|10.6|cuin|1|abbr=on}}
|-
| [[CCI (ammunition)|Speer]]
| JHP
| {{convert|88|gr|1|abbr=on}} 
|1,000&nbsp;ft/s

(305&nbsp;m/s)
| {{convert|196|ftlbf|abbr=on}} 
| {{convert|0.36|in|1|abbr=on}}
| {{convert|17.0|in|1|abbr=on}}
| {{convert|1.73|cuin|1|abbr=on}}
| {{convert|9.1|cuin|1|abbr=on}}  
|-
| [[Hornady]]
| [[Extreme Terminal Performance|XTP]]
| {{convert|90|gr|1|abbr=on}} 
|1,000&nbsp;ft/s

(305&nbsp;m/s)
| 200&nbsp;ft⋅lbf
(271 J)
| {{convert|0.44|in|1|abbr=on}}
| {{convert|11.8|in|1|abbr=on}}
| {{convert|1.73|cuin|1|abbr=on}}
| {{convert|9.1|cuin|1|abbr=on}}
|-
| Federal
| [[Full metal jacket bullet|FMJ]]
| {{convert|95|gr|1|abbr=on}}
| {{convert|955|ft/s|abbr=on}}
| {{convert|193|ftlbf|abbr=on}} 
| {{convert|0.36|in|1|abbr=on}}
| {{convert|17.0|in|1|abbr=on}}
| {{convert|1.73|cuin|1|abbr=on}} 
| {{convert|8.7|cuin|1|abbr=on}}
|-
|Underwood Ammo
|Solid copper Xtreme penetrator
|90 gr 
(5.8 g)
|1,100&nbsp;ft/s
(335&nbsp;m/s)
|242&nbsp;ft⋅lbf
(328 J)
|0.355 in
(9&nbsp;mm)
|18.0 in
(457.2&nbsp;mm)
|3.01 cu in
(49.325&nbsp;cm<sup>3</sup>)
|N/A
|}

''Key:''
*''Expansion''&nbsp;— expanded bullet diameter (ballistic gelatin)
*''Penetration''&nbsp;— penetration depth (ballistic gelatin)
*''PC''&nbsp;— permanent cavity volume (ballistic gelatin, FBI method)
*''TSC''&nbsp;— temporary stretch cavity volume (ballistic gelatin)

==Synonyms==
* United States – .380 Auto / .380 ACP / 9×17mm / 9mm Short / 9mm Browning Short
* Spain and Italy – 9mm Corto / 9mm Short 
* France – 9mm Court / 9mm Short
* Portugal – 9mm Curto / 9mm Short
* Netherlands – 9mm Kort / 9mm Short
* Bosnia – 9mm Kratak / 9mm Short
* Serbia, Croatia, and Slovenia – 9mm Kratak / 9mm short / Kratka 9 (Kratka Devetka) / Short 9 (Short Nine)
* Bulgaria and Macedonia – 9mm Kas / 9mm Short
* Germany – 9mm Kurz / 9mm Short
* Romania – 9mm Scurt / 9mm Short
* Türkiye – Kısa 9mm / Short 9mm
* United Kingdom – 9mm Browning / 9mm Browning Short / 9mm Short

==See also==
*[[9 mm caliber]]
*[[List of firearms]]
*[[List of handgun cartridges]]
*[[Table of handgun and rifle cartridges]]

==References==
{{reflist|30em}}

==External links==
*[http://www.coltautos.com/ Colt Automatic Pistols]
*[http://americanrifleman.org/ArticlePage.aspx?id=1388&cid=32 Article on Defensive Use of .380 ACP from ''American Rifleman''] {{Webarchive|url=https://web.archive.org/web/20101004064911/http://www.americanrifleman.org/ArticlePage.aspx?id=1388&cid=32 |date=2010-10-04 }}
*[https://web.archive.org/web/20100704065947/http://stoppingpower.info/tag/380-acp/ StoppingPower.Info .380 ACP vs various target videos]
*[http://www.ballisticsbytheinch.com/380auto2.html Ballistics By The Inch .380 ACP Results.]

{{John Browning}}
{{.38 Caliber}}
{{Colt's Manufacturing Company}}
{{WWIIFrenchInfWeapons}}
{{WWIIItalianInfWeapons}}

{{commons category}}

[[Category:Pistol and rifle cartridges|380 ACP]]
[[Category:Military cartridges]]
[[Category:.380 ACP firearms]]
[[Category:Colt cartridges]]
[[Category:Weapons and ammunition introduced in 1908]]