The .380 ACP (

Automatic Colt Pistol Automatic Colt Pistol (ACP) denotes various John Moses Browning cartridge designs primarily used in Colt and Fabrique Nationale de Herstal semi-automatic pistols. All of these cartridges are straight-sided and appear similar. The .32 ACP, . ...

), also known as .380 Auto, .380 Automatic, or 9×17mm, is a

rimless A rim is an external flange that is machined, cast, molded, stamped, or pressed around the bottom of a firearms cartridge. Thus, rimmed cartridges are sometimes called "flanged" cartridges. Almost all cartridges feature an extractor or headspaci ...

, straight-walled

pistol A pistol is a type of handgun, characterised by a gun barrel, barrel with an integral chamber (firearms), chamber. The word "pistol" derives from the Middle French ''pistolet'' (), meaning a small gun or knife, and first appeared in the Englis ...

cartridge that was developed by

firearm A firearm is any type of gun that uses an explosive charge and is designed to be readily carried and operated by an individual. The term is legally defined further in different countries (see legal definitions). The first firearms originate ...

s designer

John Moses Browning John Moses Browning (January 23, 1855 – November 26, 1926) was an American firearm designer who developed many varieties of military and civilian firearms, cartridges, and gun mechanisms, many of which are still in use around the world. He ...

. The cartridge headspaces on the mouth of the case.Wilson, R. K. ''Textbook of Automatic Pistols'', p. 241. Plantersville, SC: Small Arms Technical Publishing Company, 1943. It was introduced in 1908 by Colt, for use in its new

Colt Model 1903 Pocket Hammerless The Colt Model 1903 Pocket Hammerless is a .32 ACP, .32 ACP (7.65mm Browning) caliber, self-loading, semi-automatic pistol designed by John Browning and built by Colt's Manufacturing Company, Colt Patent Firearms Manufacturing Company of Hartford ...

semi-automatic, and has been a popular

self-defense Self-defense (self-defence primarily in Commonwealth English) is a countermeasure that involves defending the health and well-being of oneself from harm. The use of the right of self-defense as a legal justification for the use of Force (law), ...

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 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 A bullet is a kinetic projectile, a component of firearm ammunition that is shot from a gun barrel. They are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax; and are made in various shapes and constru ...

, 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

, and headspaces on the case mouth instead of the rim for better accuracy. These relatively low-powered designs were intended for blowback pistols which lacked a

barrel A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden stave (wood), staves and bound by wooden or metal hoops. The word vat is often used for large containers ...

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 Bolt thrust or breech pressure is a term used in internal ballistics and firearms (whether small arms or artillery) that describes the amount of rearward force exerted by the propellant gases on the Bolt (firearms), bolt or Breechblock, breech of a ...

. Blowback operation also permits the barrel to be permanently fixed to the frame, which promotes accuracy, unlike a traditional 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 P3AT and 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 A submachine gun (SMG) is a magazine (firearms), magazine-fed automatic firearm, automatic carbine designed to fire handgun cartridges. The term "submachine gun" was coined by John T. Thompson, the inventor of the Thompson submachine gun, to descri ...

s, such as the Ingram

MAC-11 The Military Armament Corporation Model 11, officially abbreviated as "M11" or "M-11", and commonly known as the MAC-11, is a machine pistol/submachine gun developed by American firearm designer Gordon Ingram at the Military Armament Corporation ...

and the Czech CZ 83.

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 World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

; Czechoslovakia (Vz.38), Hungary (FEMARU 37M), and Italy, all of whom used domestic designs, as well as The Netherlands and Yugoslavia, both of whom adopted the 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 PPK The Walther PP (, or police pistol) series pistols are blowback-operated semi-automatic pistols, developed by the German arms manufacturer Carl Walther GmbH Sportwaffen. Design The Walther PP series feature an exposed hammer, a double-action ...

were very popular with German officers. The Italian Army used the

Beretta M1934 The Beretta Model 1934 is an Italian compact, semi-automatic pistol which was issued as the service pistol of the Royal Italian Army beginning in 1934. As the standard sidearm of the Italian army it was issued to officers, NCOs and machine gun ...

, but the

Italian Air Force The Italian Air Force (; AM, ) is the air force of the Italy, Italian Republic. The Italian Air Force was founded as an independent service arm on 28 March 1923 by Victor Emmanuel III of Italy, King Victor Emmanuel III as the ("Royal Air Force ...

and

Navy A navy, naval force, military maritime fleet, war navy, or maritime force is the military branch, branch of a nation's armed forces principally designated for naval warfare, naval and amphibious warfare; namely, lake-borne, riverine, littoral z ...

stuck with the 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 The 9×19mm Parabellum (also known as 9mm Luger, 9mm NATO or simply 9mm) is a Rim (firearms)#Rimless, rimless, Centerfire ammunition, centerfire, tapered cartridge (firearms), firearms cartridge. Originally designed by Austrian firearm designer ...

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 Defense Distributed is an online, open-source hardware and software organization that develops digital schematics of firearms in CAD files, or "wiki weapons", that may be downloaded from the Internet and used in 3D printing or CNC, CNC milling a ...

's "Wiki Weapon" project to successfully 3D print a firearm.

Performance

The .380 ACP is compact and light, but has a shorter range and less

stopping power Stopping power is the supposed ability of a weapon – typically a ranged weapon such as a firearm – to cause a target (human or animal) to be incapacitated or immobilized. Stopping power contrasts with lethality in that it pertains only to a ...

than other modern pistol cartridges, depending on the load of the cartridge and manufacturer. .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 mm (.355 in) diameter bullets. The standard bullet weights are generally , , , , , , and . 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 . The table below shows common performance parameters for several .380 ACP loads. Bullet weights ranging from are the most common. Penetration depths from are available for various applications and risk assessments. ''Key:'' *''Expansion'' — expanded bullet diameter (ballistic gelatin) *''Penetration'' — penetration depth (ballistic gelatin) *''PC'' — permanent cavity volume (ballistic gelatin, FBI method) *''TSC'' — 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 nine) * United Kingdom – 9mm Browning / 9mm Browning Short / 9mm Short

References

External links

Colt Automatic PistolsArticle on Defensive Use of .380 ACP from ''American Rifleman''

StoppingPower.Info .380 ACP vs various target videos
{{commons category

380 ACP The .380 ACP ( Automatic Colt Pistol), also known as .380 Auto, .380 Automatic, or 9×17mm, is a rimless, straight-walled pistol cartridge that was developed by firearms designer John Moses Browning. The cartridge headspaces on the mouth of ...