View source for Engineering:Heckler & Koch USP

{{Infobox weapon
| name               = Heckler & Koch USP9
| image              = First-year_H&K_USP_9mm_(32415150000)_modified.png
| image_size         = 300
| caption            = Heckler & Koch USP9
| origin             = Germany
| type               = [[Engineering:Semi-automatic pistol|Semi-automatic pistol]]
<!-- Type selection -->| is_ranged          = yes
<!-- Service history -->| service            = 1993–present
| used_by            = See ''Users''
| wars               = <!-- Production history -->
| designer           = Helmut Weldle
| design_date        = 1989–1992
| manufacturer       = Heckler & Koch, EAS<ref>{{cite web|url=http://www.eas.gr/en/71/guns-weapons|title=eas.gr|access-date=2015-06-02|archive-url=https://web.archive.org/web/20160306041515/http://www.eas.gr/en/71/guns-weapons|archive-date=2016-03-06|url-status=live}}</ref>
| production_date    = 1993–present
| number             = 
| variants           = See ''Variants'':
<!-- General specifications -->| weight             = {{convert|748|g|abbr=on}} without [[Engineering:Magazine (firearms)|magazine]]
| length             = {{convert|194|mm|in|abbr=on}}
| part_length        = {{convert|108|mm|in|abbr=on}}
| width              = {{convert|32|mm|in|abbr=on}}
| height             = {{convert|135|mm|in|abbr=on}}
<!-- Ranged weapon specifications -->| cartridge          = * [[Engineering:9×19mm Parabellum|9×19mm Parabellum]]
* .357 SIG (''Compact version'' only)
* .40 S&W
* .45 ACP
| action             = [[Engineering:Recoil operation#Short recoil operation|Short recoil]]
| rate               = [[Engineering:Semi-automatic firearm|Semi-automatic]]
| velocity           = 
| range              = 50 m
| max_range          = 100 m
| feed               = Detachable box magazine; capacities:
* 15 rounds (9x19mm Parabellum)
* 13 rounds (.40 S&W and .357 SIG)
* 12 rounds (.45 ACP)
| sights             = Patridge, "3-dot" type
<ref>{{cite web | url=https://www.heckler-koch.com/en/products/military/pistols/usp/usp/technical-data.html | title=Heckler & Koch :: Technical Data &#124; USP }}</ref>
}}

The '''USP''' (''Universelle Selbstladepistole'' or "universal self-loading pistol") is a [[Engineering:Semi-automatic pistol|semi-automatic pistol]] developed in Germany by Heckler & Koch GmbH (H&K) as a replacement for the P7 series of handguns.

==History==
Design work on a new family of pistols commenced in September 1989, focused primarily on the United States commercial and law enforcement markets. USP prototypes participated in rigorous testing alongside H&K's entry in the Offensive Handgun Weapon System (OHWS) program requested by the U.S. Special Operations Command (USSOCOM), which would later result in the Mk 23 Mod 0. The USP prototypes were then refined in 1992, based on input from the OHWS trials, and the design was finalized in December of the same year. The USP was formally introduced in January 1993 with the '''USP40''' model (the base version) chambered for the increasingly popular .40 S&W cartridge, followed soon by the '''USP9''' (using the [[Engineering:9×19mm Parabellum|9×19mm Parabellum]] cartridge), and in May 1995—the '''USP45''' (caliber .45 ACP).
In contrast to the P7, P9S, and VP70Z designs, the USP uses a more conventional Browning-style cam-locked action, similar to that used in the [[Engineering:Browning Hi-Power|Hi-Power]], but with a [[Chemistry:Polymer|polymer]] frame.<ref name="hkusa_usp" /><ref name="hk_usp_specs">{{cite web| last = Heckler & Koch Global| title = USP: Specifications| url = http://www.heckler-koch.de/HKWebText/detailPara/1925/135/4/21/244| access-date = 2008-08-03| archive-url = https://web.archive.org/web/20080912213547/http://www.heckler-koch.de/HKWebText/detailPara/1925/135/4/21/244| archive-date = 2008-09-12| url-status = live}}</ref>

==Design details==
The USP is a semi-automatic pistol with a mechanically locked breech using the [[Engineering:Recoil operation#Short recoil operation|short recoil]] method of operation. This rather conventional lock-up system has a large rectangular lug over the barrel's [[Engineering:Chamber (firearms)|chamber]] that rides into and engages the ejection port cut-out in the slide. When a cartridge is fired, pressures generated by the ignited powder drive the cartridge casing back against the breech face on the slide, driving back both the barrel and slide as they remain locked together in the manner described above. After {{convert|3|mm|abbr=on|2}} of unrestricted rearward travel, the projectile leaves the barrel and the gas pressures drop to a safe level. A shaped lug on the underside of the barrel chamber comes into contact with a hooked locking block at the end of the steel recoil spring guide rod, lowering the rear end of the barrel and stopping the barrel's rearward movement. The recoil spring assembly is held in place by the [[Engineering:Slide stop|slide stop]] lever's axis pin and a round cut-out at the front of the slide. For enhanced reliability in high-dust environments, the locking surface on the front top of the barrel's locking lug is tapered with a forward slope. This tapered surface produces a camming action which assists in positive lock-up in the presence of heavy fouling and debris.

One of the distinguishing features of the USP is the mechanical recoil reduction system. It consists of a short additional spring located within the main recoil spring on the breech end of the recoil spring assembly. Designed primarily to reduce wear on the pistol's components, the system also lowers the peak recoil forces felt by the shooter. The design with two springs allows the system to work with different kinds of ammunition without requiring any adjustments. Unlike similar systems employed in other guns, the USP design does not incorporate a hydraulic damper and requires no maintenance. Using a similar recoil reduction system, the H&K Mk 23 pistol fired more than 30,000 high pressure (+P) cartridges and 6,000 proof loads without damage or excessive wear to any major components. Abuse and function-testing of USPs have seen more than 20,000 rounds of .40 S&W fired without a component failure. MILSPEC environmental tests were conducted in high and low temperatures, in mud, immersed in water and in salt spray. In one particular test, a bullet was deliberately lodged in the barrel and another bullet was fired to clear the obstruction. The barrel was successfully cleared with only minor structural deformation and continued to produce consistent groups when test fired for accuracy. The recoil reduction system is not present on the USP Compact models, which instead use a simple polymer bushing as a buffer to reduce slide on frame impact.<ref name="Kokalis">pp253.</ref>

Major metal components on both the USP and Special Operations Pistol are corrosion-resistant. Outside metal surfaces such as the steel slide are protected by a proprietary "Hostile Environment" [[Chemistry:Nitriding|nitride]] finish.<ref name="hk_usp" /> Internal metal parts, such as springs, are coated with a Dow Corning anti-corrosion chemical to reduce friction and wear.<ref name="remtek_usp">
{{cite web| last = Remtek| title = Heckler & Koch Universal Self-loading Pistol (USP)| url = http://www.remtek.com/arms/hk/civ/usp/usp.htm| access-date = 2008-08-03| archive-url = https://web.archive.org/web/20080816034113/http://www.remtek.com/arms/hk/civ/usp/usp.htm| archive-date = 2008-08-16| url-status = live}}</ref>{{Self-published inline|date=February 2015|certain=y}}

The USP is composed of a total of 54 parts and is broken down into 7 major components for maintenance and cleaning: the barrel, slide, recoil spring, recoil spring guide rod, frame, slide stop and magazine. This is done by retracting the slide back to align the slide stop axis pin with the disassembly notch on the left side of the slide and withdrawing the axis pin.

==Variants==
The USP was originally built around the .40 S&W cartridge, but a [[Engineering:9×19mm Parabellum|9×19mm Parabellum]] was introduced at the same time. In May 1995, Heckler & Koch introduced a .45 ACP variant. The '''USP Compact''' series was introduced in 1996 and is available in 9&nbsp;mm Parabellum, .40 S&W, .45 ACP, and, exclusively to the Compact model, .357 SIG. Other variants of the standard USP include the '''USP Tactical''', '''USP Expert''', '''USP Match''', '''USP Elite''' and the standard sidearm of the German Armed Forces (Bundeswehr)—the '''P8'''. The USP Tactical .45 ACP variant is also in limited use by the Bundeswehr, designated as the P12.

One of the unique features of the USP is the wide variety of the trigger styles available, which may be quickly swapped. There are nine commercially available modifications (called "variants" by HK).<ref name="hk_usp_specs" /><ref name="hk_usp" />

By using a modular approach to the internal components,<ref name="hkusa_usp">{{cite web
  | last = Heckler & Koch USA
  | title = Heckler & Koch USP Pistols
  | url = http://www.hecklerkoch-usa.com/usp_general.html
  | access-date = 2008-07-28 |archive-url = https://web.archive.org/web/20080410200901/http://www.hecklerkoch-usa.com/usp_general.html <!-- Bot retrieved archive --> |archive-date = 2008-04-10}}</ref> the control functions of the USP can be switched from the left to the right side of the pistol for left-handed shooters. The USP can also be converted from one type of trigger/firing mode to another. This includes combination of double-action and single-action (DA/SA) and double-action only (DAO) modes.<ref name="hk_usp">{{cite web
  | last = Heckler & Koch Global
  | title = USP
  | url = http://www.heckler-koch.de/HKWebText/detailProd/1925/135/4/21
  | access-date = 2008-07-28
  | archive-url = https://web.archive.org/web/20080727203249/http://www.heckler-koch.de/HKWebText/detailProd/1925/135/4/21
  | archive-date = 2008-07-27
  | url-status = dead
  }}</ref>

In addition to a wide selection of trigger/firing modes, the USP has an ambidextrous magazine release lever that is shielded by the trigger guard from inadvertent actuation. The rear of the USP grip is stepped, and combines with the tapered magazine to allow for rapid reloading. Finger recesses in the grip frame also aid in magazine removal. On 9&nbsp;mm and .40 caliber USPs, magazines are constructed of polymer reinforced with stainless steel. Magazines on the USP45 are all-metal. All USP magazines will drop free of the pistol frame when the magazine release is depressed. Also, the USP does not have a magazine lockout feature (also known as a magazine disconnector).  Thus, it is possible to fire a chambered round even with the magazine removed. An extended slide release lever is positioned to allow easy operation without changing the grip of the shooting hand.

;Variants 1 and 2 (double action/single action, decocking and safety lever)
:Variants 1 (lever on left) and 2 (lever on right) allow the user to carry the pistol in a single-action mode (cocked and locked) with the manual safety engaged. This same pistol, without modification, can be carried in double-action mode, with or without the manual safety engaged, and with the benefit of a decocking lever.

;Variants 3 and 4 (double action/single action, decocking lever, but no safety)
:Variants 3 (lever on left) and 4 (lever on right) provide the user with a frame-mounted decocking lever that does not have the "safe" position. This combination only allows the hammer to be lowered from SA position to DA position. It does not provide the "safe" position to prevent the pistol from firing when the trigger is pulled.

;Variants 5 and 6 (double action only, with safety lever)
:Variants 5 (lever on left) and 6 (lever on right) operate as double-action-only pistols, with a bobbed hammer always returning to the DA position (forward) after each shot is fired. To fire each shot, the trigger must be pulled through the smooth DA trigger pull. Variants 5 and 6 have a manual safety lever.

;Variant 7 (Law Enforcement Modification, no control lever)
:Developed for the U.S. government, the Law Enforcement Modification (LEM) is a double-action only model with a unique trigger mechanism. This mechanism improves the double-action trigger performance and reduces the weight of the double-action trigger pull to {{convert|8|lbf}}, uses a stronger hammer spring, and shortens the trigger reset.

;Variant 8
:Never produced.

;Variants 9 and 10 (double-action/single-action, safety lever, but no decocker)
:Variants 9 (lever on left) and 10 (lever on right) allow the shooter to carry the pistol in a single-action mode (cocked and locked) with the manual safety engaged. This same pistol, without modification, can be carried in double-action mode (hammer down), with or without the manual safety engaged. The double-action mode offers a second-strike/double-action capability in case of a misfire. The control lever has no decocking function on variants 9 and 10, so one would have to lower the hammer manually (or keep the safety on, remove the magazine, and eject any round in the chamber before lowering the hammer).

===USP Custom Sport===
Almost identical to the standard USP, the Custom sport is aimed at target and practical shooting users. The Custom Sport has a match grade barrel, match trigger and adjustable sights.

===USP Compact===
[[Image:HKUSPCOMPACT40.jpg|thumb|right|The USP Compact in .40 S&W.]]
The first USP Compact models appeared in 1996. These are scaled-down USPs, and are available in all the same cartridges as the full size version, and additionally the .357 SIG. Due to the smaller size of the frame, magazines for the Compact variant may have a handgrip extension to better accommodate the shooter's hand. Standard flat floorplates are also available for the USP Compact magazines. The USP Compact comes standard with a bobbed hammer equipped with a flat rubber external thumb grip. This reduces possible snag from the hammer on a holster or clothing while the pistol is being drawn, but still allows the USP Compact to be cocked from a decocked position even in the absence of a spurred hammer. This can be done since decocking the weapon does not fully drop the hammer, leaving it in a somewhat "half-cocked" state.

The USP Compact cannot be cocked from a dry-fired position as the hammer will be flush to the back of the slide. However, the operator could pull the trigger approximately halfway back in a dry-fired position to put the hammer in a half-cocked state, allowing the hammer to be fully cocked with the thumb. The P10, designed for German military and police units, is a USP Compact with the addition of a spurred hammer. This hammer can also be installed onto a normal USP Compact. In addition to the variants previously described for the full size USP, an ambidextrous safety is available from the manufacturer as a separate part. After installation, the USP Compact effectively becomes a right or left-handed firearm with respect to the decocker and manual safety functions. Heckler & Koch do not produce caliber conversions, but barrels for .357 SIG and .40 S&W are available from HK and from third-party manufacturers.

===USP Tactical===
[[File:HK USP Tactical 9mmSD RMP PGK.jpg|thumb|right|HK USP9SD (tactical) of the Pasukan Gerakan Khas, fitted with Brügger & Thomet sound suppressor, Picatinny pistol rail and Aimpoint Micro T-1.]]
The USP Tactical (9mm Parabellum, .40 S&W, .45 ACP) incorporates fully adjustable suppressor height sights, an extended, threaded barrel with [[O-ring]], and a [[Engineering:Match grade|match grade]] trigger with adjustable trigger stop. Prior to 2015, there was no USP Tactical model in 9mm. Instead, HK offered the regular "USP9" variant with an extended, threaded barrel and suppressor height sights as the "USP9SD" model.<ref>{{cite web  |title=New HK Handguns for 2015  |date=January 19, 2015  |access-date=January 19, 2015  |url=http://hk-usa.com/new-hk-handguns-2015/  |archive-url=https://web.archive.org/web/20150319164017/http://hk-usa.com/new-hk-handguns-2015/  |archive-date=March 19, 2015  |url-status=dead  }}</ref> Sound suppressors designed for the USP Tactical are available from Brügger & Thomet and Knight's Armament. A unique characteristic of the USP Tactical is that the barrel is [[Engineering:Screw thread#Standard threads|left-hand threaded]] (counter-clockwise to tighten), which makes the pistol incompatible with suppressors designed for the MK23 Mod 0.<ref name="USPManual">{{cite book  | last = Heckler & Koch USA  | title = HK USP, USP Compact Pistol & USP Specialty Pistols Operators Manual  | date = March 2007  | url = http://www.hk-usa.com/-images/shared/USP%20Manual%20REV%203-07.pdf  | page = 40  | url-status = dead  | archive-url = https://web.archive.org/web/20110711172218/http://www.hk-usa.com/-images/shared/USP%20Manual%20REV%203-07.pdf  | archive-date = 2011-07-11  }}</ref>

The KSK of the German Army and the German Navy Kampfschwimmer use the USP Tactical under the designation "P12".

===USP Compact Tactical===
[[Image:HK USP-CT.jpg|thumb|right|HK USP Compact Tactical .45 ACP equipped with a SureFire flashlight]]

The USP45CT Compact Tactical is a .45 caliber handgun developed for U.S. special operations. It incorporates features of the full-size USP45 Tactical pistol, but is more concealable. Features include an extended, threaded O-ring barrel with polygonal bore profile and suppressor height sights, which may limit the use of holsters designed for standard USP Compact pistols. The USP CT is available in .45 ACP only.<ref name="Lee2014">{{cite book|last=Lee|first=Jerry|title=Gun Digest 2015|url=https://books.google.com/books?id=nMyRBAAAQBAJ&pg=PT1392|date=15 July 2014|publisher=F+W Media|location=Iola, Wisconsin|isbn=978-1-4402-3918-2|page=1392}}</ref>

===USP Expert===
[[File:HK USP Elite and Expert 9mm with Merkle Tuning weights (20965366061).jpg|thumb|right|HK USP Elite and Expert 9mm with Merkle Tuning weights]]
[[File:Heckler & Koch USP Expert .45 "Variant 1".jpg|thumb|USP Expert .45 V1 with cartridge loaded backwards in magazine]]
The USP Expert (9&nbsp;mm Parabellum, .40 S&W, .45 ACP) was introduced in 1998, and includes all the features of the Tactical, but instead of the extended barrel being threaded and protruding from the slide, the Expert uses a longer slide to accommodate the extended barrel. The larger slide adds weight to help reduce muzzle flip and felt recoil. The Expert has adjustable target sights similar to the USP Match, Elite and Tactical, but as on the Elite, the dovetail of the rear sight is lowered into the frame.  The bobbed hammer was a factory option for the Expert if it was to be used in IPSC for the Standard Division because the original version "in its ready condition" did not fit the box for Standard division in IPSC.

===USP Match===
[[File:H&K USP Elite, Expert, 9mm (21090595098).jpg|thumb|A USP Match is shown alongside USP Elite and Expert with Merkle Tuning weight]]
The USP Match (9&nbsp;mm Parabellum, .40 S&W, .45 ACP) has the same features offered on the Expert, except for a barrel weight that replaces the elongated slide found on the Expert. This weight is said to provide a recoil counterbalance to aid in target tracking.{{Citation needed|date=April 2021}}
It was discontinued in 1999.

===USP Elite===
[[File:H&K USP Elite 45 (31981312683).jpg|thumb|right|USP Elite 45]]
The USP Elite (9&nbsp;mm Parabellum, .45 ACP) combines the characteristics of the Expert with a 6.02 in (153&nbsp;mm) barrel<ref name="heckler-koch.com">{{cite web|url=http://www.heckler-koch.com/en/products/sport/sport/usp-elite/usp-elite/overview.html|title=Heckler & Koch :: Product Overview - USP Elite|work=heckler-koch.com|access-date=2015-08-26|archive-url=https://web.archive.org/web/20150924025705/http://www.heckler-koch.com/en/products/sport/sport/usp-elite/usp-elite/overview.html|archive-date=2015-09-24|url-status=dead}}</ref> and a hand-fitted 9.25 in (235&nbsp;mm) extended slide. The model was designed as a target pistol and has not been adopted by any law-enforcement agency or military organization.

==Equipment==
[[Image:HK USP 45 surrounded by .45 caliber Hornady TAP (+P) jacketed hollow point rounds.jpg|thumb|right|USP45 with SureFire light attachment]]
The USP has an accessory rail at the front of the frame for attachments of aftermarket equipment such as laser sights and [[Engineering:Tactical light|weapon lights]]. The rail is a proprietary design, and the number of accessories available is extremely limited. Aftermarket adapters providing a standard Picatinny rail are available for both USP and USP Compact models.

==Testing==
The USP was developed at the same time as the SOCOM MK23; the pistol underwent much of the same testing. The barrel is cold-forged from chromium steel for increased service life. USP barrels after November 1994 use a [[Engineering:Polygonal rifling|polygonal profile]]; 1994 and earlier models use traditional 'land and grooves' rifling. During testing, a bullet was deliberately lodged in a USP barrel. Another cartridge was then fired into the obstructing bullet. The second bullet cleared the barrel, resulting in a barely-noticeable bulge. The pistol was then fired for accuracy, and the resulting group measured less than 4 inches at 25 meters.<ref name="streetpro_torture">
{{cite web
  | last = Streetpro
  | title = Heckler and Koch USP Torture Test
  | url = http://www.streetpro.com/usp/torture.html
  | access-date = 2008-08-03
  | archive-url = https://web.archive.org/web/20080704130114/http://www.streetpro.com/usp/torture.html
  | archive-date = 2008-07-04
  | url-status = live
  }}
</ref>

Temperature testing required the USP be frozen to −42&nbsp;°C and fired, frozen again, then be heated to 67&nbsp;°C and fired. These temperature tests were continually repeated with no adverse effects on the USP.<ref name="streetpro_torture" />

The gun was also subjected to NATO MILSPEC mud and rain tests; it passed without difficulty. Water immersion and salt spray also presented no problems. German Navy combat divers used the USP for years without any signs of corrosion.

Safety testing exceeded the ANSI/[[Organization:Sporting Arms and Ammunition Manufacturers' Institute|SAAMI]] requirements adopted in May 1990. These included dropping a USP with a primed cartridge and decocked hammer on a variety of hard surfaces without discharging. The USP surpassed these commercial requirements, as well as German Army and police tests, including repeated drop tests from six feet (1.8 m)<!-- surely German Army tests would be a round number of metres like 2 m rather than '6 ft'? -->, hammer first, onto a steel backed concrete slab. [[Engineering:Proof test|Proof round]] firing resulted in no cracks, deformations, or increase in head space. Attempts to fire the USP pistol with an unlocked breech proved unsuccessful.

Testing with a variety of ammunition proved the USP meets these high standards. During the USP testing phase, the recoil-reduction system reduces the force on the USP grip to approximately 300 [[Newton (unit)|newton]]s (67 pounds-force). Peak force shock on competing .40 caliber polymer and metal framed pistols was around 5,000 newtons (1,100 pounds-force). The primary benefit of low peak shock is a decrease in wear and tear on pistol components, a great concern with the +P cartridge in 9&nbsp;mm, .40 S&W, and .45 ACP. Reduction of peak shock forces also contributes to softer recoil for the shooter, although these "felt recoil" values are subjective.

==Service==
[[Image:Km2000.jpg|thumb|right|KM2000 knife & P8 pistol of the Bundeswehr.]]
The USP was adopted in Germany by the ''Bundeswehr'' (German armed forces) as the P8 in 1994.<ref name="bundeswehr">
{{cite web |last=Bundeswehr: streitkraeftebasis |title=Pistole P8 |url=http://www.streitkraeftebasis.de/portal/a/streitkraeftebasis/kcxml/04_Sj9SPykssy0xPLMnMz0vM0Y_QjzKL9443CXMBSYGZIab6kRCGJVws2BIqBlQXlJKq7-uRn5uq760foF-QGxpR7uioCADJyAXC/delta/base64xml/L2dJQSEvUUt3QS80SVVFLzZfS180Vko!?yw_contentURL=%2F01DB040000000001%2FW26A9FBX051INFODE%2Fcontent.jsp |url-status=live |archive-url=https://web.archive.org/web/20081229182440/http://www.streitkraeftebasis.de/portal/a/streitkraeftebasis/kcxml/04_Sj9SPykssy0xPLMnMz0vM0Y_QjzKL9443CXMBSYGZIab6kRCGJVws2BIqBlQXlJKq7-uRn5uq760foF-QGxpR7uioCADJyAXC/delta/base64xml/L2dJQSEvUUt3QS80SVVFLzZfS180Vko!?yw_contentURL=%2F01DB040000000001%2FW26A9FBX051INFODE%2Fcontent.jsp |archive-date=2008-12-29 |access-date=2008-07-28}} (in German)
</ref> The P8 has minor differences from the standard USP model: translucent magazines, a reversed safety/decocker lever (on the P8, down indicates 'safe', and up indicates 'fire' — the opposite of the standard USP), and the 'S' and 'F' letters are printed onto the frame instead of onto the lever. The P8 has a traditional lands-and-grooves barrel instead of a [[Engineering:Polygonal rifling|polygonal barrel]].<ref name="hk_p8">
{{cite web
  | last = Heckler & Koch Global
  | title = Pistole P8
  | url = http://www.heckler-koch.de/HKWebText/detailProd/1925/121/4/21
  | access-date = 2008-07-28
  | archive-url = https://web.archive.org/web/20080901200846/http://www.heckler-koch.de/HKWebText/detailProd/1925/121/4/21
  | archive-date = 2008-09-01
  | url-status = live
  }}
</ref>

The P10, adopted by many German State Police forces, is a USP Compact with the addition of a spurred hammer.<ref name="hk_p10">
{{cite web
  | last = Heckler & Koch Global
  | title = Pistole P10
  | url = http://www.heckler-koch.de/HKWebText/detailProd/1925/120/4/21
  | access-date = 2008-07-28
  | archive-url = https://web.archive.org/web/20080908202130/http://www.heckler-koch.de/HKWebText/detailProd/1925/120/4/21
  | archive-date = 2008-09-08
  | url-status = live
  }}
</ref> Both the P8 and P10 are chambered in 9×19mm Parabellum (9mm NATO) only.<ref name="hk_p8" /><ref name="hk_p10" />

In 1998, the H&K USP Compact with the LEM trigger action, in .40 S&W, was adopted by the United States Immigration and Naturalization Service as the duty sidearm for its Special Agents and plainclothes officers. In 2004, after the I&NS's criminal investigations branch merged with the U.S. Customs Service's Office of Investigations into the U.S. Department of Homeland Security's Homeland Security Investigations, the former I&NS Special Agents continued to carry the USP Compact. New duty pistols, the SIG Sauer Model P229 DAK, in .40 S&W, were eventually issued to the HSI Special Agents after new pistol contracts were awarded by the DHS.<ref name="Former I&NS Special Agent">Former I&NS Special Agent</ref>

On August 24, 2004, SIG Sauer and Heckler & Koch/HK Defense won major pistol contracts with the United States Department of Homeland Security. The contract was valued at $26.2 million.<ref name="dhs">{{cite press release
 |title       = Department Of Homeland Security Awards Handgun Contracts
 |publisher   = Department of Homeland Security
 |date        = 2004-08-24
 |url         = https://www.dhs.gov/xnews/releases/press_release_0493.shtm
 |access-date  = 2008-07-28
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20080726181730/http://www.dhs.gov/xnews/releases/press_release_0493.shtm
 |archive-date = 2008-07-26
}}</ref> The HK pistol models chosen were the HK P2000 US, HK P2000 SK Subcompact, and the USP Compact/LEM (Law Enforcement Modification).<ref>
{{cite news
  | last = Crane
  | first = David
  | title = SIGARMS and Heckler & Koch/HK Defense Win Major Pistol Contracts with DHS
  | publisher = Defense Review
  | date = 2004-08-29
  | url = http://www.defensereview.com/modules.php?name=News&file=article&sid=779
  | access-date = 2008-07-28
  | archive-url = https://web.archive.org/web/20071031093643/http://www.defensereview.com/modules.php?name=News&file=article&sid=779
  | archive-date = 2007-10-31
  | url-status = live
  }}
</ref> The LEM trigger is HK's version of SIG's DAK trigger, and vice versa. According to the company, the LEM trigger allows for faster follow-up shots (repeat shots) on target than a standard double-action-only system. This is due to a lighter trigger pull (7.3–8.5 lbf) and shorter trigger reset than standard DAO trigger systems. The LEM trigger uses a two-piece "pre-cocked hammer" composed of a cocking piece and an external hammer. The hammer is pre-cocked as a round is chambered (slide is cycled). The LEM system supposedly also provides reliable primer ignition, since it uses a stronger hammer spring.

The LEM trigger can be installed on existing USP Compact pistols acquired before the LEM trigger came on the market—either by a certified gunsmith or by sending the pistol to Heckler & Koch. In addition, the USP Compact pistol can retain its external safety with the LEM trigger—making it the only modified double-action pistol with an external safety.

==Users==
<!--READ FIRST: This section is for cited entries only. Please do not add entries into this list without a citation from a reliable source. All entries without a citation will be removed. Thank you.-->

{| class="wikitable" style="font-size: 95%;"
! width="120px"| Country
! Organization name
! Model
! width="50px"| Caliber
! Reference
|-
| rowspan="4" |{{flag|Australia}}
|Australian Federal Police Air Security Officers
|align="center"| USP Tactical
|align="center"| 9mm
|align="center"|<ref>{{cite web|url=http://www.ssaa.org.au/stories/political-up-in-arms.html|title=Up in arms|work=ssaa.org.au|access-date=2010-10-06|archive-url=https://web.archive.org/web/20110225071646/http://www.ssaa.org.au/stories/political-up-in-arms.html|archive-date=2011-02-25|url-status=live}}</ref>
|-
|Western Australia Police Tactical Response Group
|align="center"| USP Tactical
|align="center"| .45 ACP
|align="center"|<ref>{{Cite web |url=http://www.couriermail.com.au/news/man-dead-after-perth-standoff/story-e6freomx-1226044067889 |title=Man dead after Perth standoff &#124; the Courier-Mail |access-date=2011-04-29 |archive-url=https://web.archive.org/web/20120913061007/http://www.couriermail.com.au/news/man-dead-after-perth-standoff/story-e6freomx-1226044067889 |archive-date=2012-09-13 |url-status=live }}</ref>
|-
|Australian Army Special Operations Command
|align="center"| USP Tactical
|align="center"| 9mm<ref>{{Cite web |url=http://www.4rar.com/TagEast.pdf |title=Archived copy |access-date=2014-09-12 |archive-url=https://web.archive.org/web/20140912092334/http://www.4rar.com/TagEast.pdf |archive-date=2014-09-12 |url-status=dead }}</ref>
|align="center"|<ref name="kemp2008">{{cite web |url=http://www.asianmilitaryreview.com/CurrentIssue/dl.php?filename=200901021211061.pdf |title=Individual Weapons - Combat Pistols: Poised for a Shift |author=Kemp, Ian |date=December 2008 |publisher=Asian Military Review |access-date=2009-10-01 |url-status=dead |archive-url=https://www.webcitation.org/6JxyuxKqy?url=http://www.scribd.com/doc/96608601/Individual-weapons-combat-pistols |archive-date=2013-09-28 }}</ref><ref>{{cite web |url=http://www.australiandefender.com.au/stories/tagct.pdf |title=Archived copy |access-date=2011-05-27 |url-status=dead |archive-url=https://web.archive.org/web/20110627023935/http://www.australiandefender.com.au/stories/tagct.pdf |archive-date=2011-06-27 }}</ref><ref>{{Cite web |url=http://www.militarytrophies.com.au/gallery51a.jpg |title=Archived copy |access-date=2014-09-12 |archive-url=https://web.archive.org/web/20150301005229/http://www.militarytrophies.com.au/gallery51a.jpg |archive-date=2015-03-01 |url-status=dead }}</ref>
|-
|Queensland Police Special Emergency Response Team
|align="center"| USP Tactical
|align="center"| .45 ACP
|align="center"|<ref>{{cite web |url=http://www.police.qld.gov.au/Resources/Internet/join/documents/LR_SERT_160709.pdf |title=Archived copy |access-date=2010-11-08 |url-status=dead |archive-url=https://web.archive.org/web/20110304205320/http://www.police.qld.gov.au/Resources/Internet/join/documents/LR_SERT_160709.pdf |archive-date=2011-03-04 }}</ref><ref>{{cite web|url=http://www.qt.com.au/story/2010/11/11/raaf-base-simulated-attack-training-exercise/|title=RAAF base hold simulated training|work=Queensland Times|access-date=2011-05-27|archive-url=https://web.archive.org/web/20110810052447/http://www.qt.com.au/story/2010/11/11/raaf-base-simulated-attack-training-exercise/|archive-date=2011-08-10|url-status=dead}}</ref>
|-
| rowspan="2" |{{flag|Denmark}}
|Danish Police
| align="center" | USP Compact
| align="center" | 9&nbsp;mm
| align="center" |<ref name="knowncrimes.dk">{{cite web|publisher=knowncrimes.dk |title=Politiets Magtanvendelser |url=http://www.knowncrimes.dk/pmagtanvendelser.html |access-date=2010-04-12 |language=da }}{{dead link|date=March 2017 |bot=InternetArchiveBot |fix-attempted=yes }}</ref><ref name="BT.dk">{{cite web | publisher = BT | title = Politiets Våben | date = 30 May 2007 | url = http://www.bt.dk/krimi/politiets-vaaben | access-date = 2010-04-12 | language = da | archive-url = https://web.archive.org/web/20120223135919/http://www.bt.dk/krimi/politiets-vaaben | archive-date = 2012-02-23 | url-status = live }}</ref>
|-
|''Jægerkorpset'' of the Royal Danish Army
| align="center" | USP9 SD
| align="center" | 9&nbsp;mm
| align="center" |<ref>{{cite web |url=http://www.forsvaret.dk/FKO/Nyt%20og%20Presse/Publikationer/Forsvarets%20Personaleblad/Documents/Forsvaret_2007_nr_2_web.pdf |title=Archived copy |access-date=2010-12-11 |url-status=dead |archive-url=https://web.archive.org/web/20111220021754/http://www.forsvaret.dk/FKO/Nyt%20og%20Presse/Publikationer/Forsvarets%20Personaleblad/Documents/Forsvaret_2007_nr_2_web.pdf |archive-date=2011-12-20 }}</ref>
|-
|{{flag|Egypt}}
|Central Security Forces Sa'ka Forces
Unit 777 
|align="center"| -
|align="center"| 
|align="center"|<ref name ='SAS 26'/>
|-
|{{flag|Estonia}}
|Estonian Armed Forces
|align="center"| USP
|align="center"| 9&nbsp;mm
|align="center"|<ref>{{cite news| last = Kommersant| title = Estonian Army Replaces Pistol of Makarov| date = 2005-12-27| url = http://www.kommersant.com/page.asp?id=-7846| access-date = 2008-07-28| url-status = dead| archive-url = https://web.archive.org/web/20081229191713/http://www.kommersant.com/page.asp?id=-7846| archive-date = 2008-12-29}}</ref>
|-
|rowspan="2"|{{flag|France}}
|French Navy (PA HK Marine)
|align="center"| USP Compact
|align="center"| -
|align="center"|<ref name="frenchnavy">{{cite web | publisher = Le ministère de la Défense | title = Pistolet automatique - HK USP Compact Marine National | url = http://jdb.marine.defense.gouv.fr/post/2009/01/24/Les-cadets-%C3%A9miratis-d%C3%A9couvrent-les-armes-de-la-marine-fran%C3%A7aise | access-date = 2009-01-22 | language = fr | url-status = dead | archive-url = https://archive.today/20090129124112/http://jdb.marine.defense.gouv.fr/post/2009/01/24/Les-cadets-%C3%A9miratis-d%C3%A9couvrent-les-armes-de-la-marine-fran%C3%A7aise | archive-date = 2009-01-29 }}</ref>
|-
|''Recherche Aéroportée et Actions Spécialisées'' (RAPAS)
|align="center"| USP Tactical
|align="center"| -
|align="center"|<ref name="frencharmy">{{cite web| last = Le ministère de la Défense| title = Pistolet automatique - HK USP| url = http://www.defense.gouv.fr/terre/decouverte/materiels/materiels_specifiques/hk_usp| access-date = 2008-08-16| language = fr| archive-url = https://web.archive.org/web/20071014003703/http://www.defense.gouv.fr/terre/decouverte/materiels/materiels_specifiques/hk_usp| archive-date = 2007-10-14| url-status = live}}</ref>
|-
|rowspan="2"|{{flag|Germany}}
|''Bundeswehr''
|align="center"| P8<br>USP Tactical (P12)
|align="center"| 9mm (P8), .45 ACP (P12)
|align="center"|<ref name="bundeswehr" />
|-
|''Landespolizei''
|align="center"| USP Compact (P10)
|align="center"| 9mm
|align="center"|<ref>{{cite web|url=http://www.heckler-koch.de/HKWebText/detailProd/1925/120/4/21|title=Heckler & Koch :: Home|work=heckler-koch.de|access-date=2008-07-28|archive-url=https://web.archive.org/web/20080908202130/http://www.heckler-koch.de/HKWebText/detailProd/1925/120/4/21|archive-date=2008-09-08|url-status=live}}</ref>
|-
|{{flag|Georgia}}
|Georgian Armed Forces
|align="center"| USP
|align="center"| 9&nbsp;mm
|align="center"|<ref>{{cite web|url=http://geo-army.ge/index.php?option=com_content&view=article&id=9&Itemid=9&lang=en |title=Armament of the Georgian Army |publisher=Geo-army.ge |access-date=2013-01-01 |url-status=dead |archive-url=https://web.archive.org/web/20120309192408/http://geo-army.ge/index.php?option=com_content&view=article&id=9&Itemid=9&lang=en |archive-date=2012-03-09 }}</ref>
|-
|{{flag|Greece}}
|Hellenic Army Hellenic Police
| align="center" | USP 
| align="center" | 9mm
| align="center" | <ref>{{cite web |url=https://www.eas.gr/en/product-category-en/guns-amp-weapons/ |title=Guns and Weapons| website=eas.gr |publisher=EAS |access-date=28 October 2022}}</ref>
|-
|{{flag|Ireland}}
|Defence Forces
| align="center" | USP family
| align="center" | 9mm
| align="center" |<ref>{{cite news| last = Lavery| first = Don| title = Defence Forces to turn 'tomb raiders'| publisher = Independent.ie| date = 2006-09-02| url = http://www.independent.ie/national-news/defence-forces-to-turn-tomb-raiders-76402.html| access-date = 2008-07-28| archive-url = https://web.archive.org/web/20111219202143/http://www.independent.ie/national-news/defence-forces-to-turn-tomb-raiders-76402.html| archive-date = 2011-12-19| url-status = live}}</ref><ref name="2007 magazine">{{cite journal|last1=Huges|first1=Capt Brian|title=Taking Aim|journal=An Cosantóir.|date=April 2007|volume=67|issue=4|page=6|url=http://www.dfmagazine.ie/site-assets/uploads/Vol._67_No._4_-_Apr_2007.pdf|access-date=14 November 2016|archive-url=https://web.archive.org/web/20170202001333/http://www.dfmagazine.ie/site-assets/uploads/Vol._67_No._4_-_Apr_2007.pdf|archive-date=2 February 2017|url-status=dead}}</ref>
|-
|{{flag|Japan}}
|Japanese Special Forces Group
|align="center"| -
|align="center"| -
|align="center"|<ref name="Report">{{cite web |archive-url=https://web.archive.org/web/20130128031902/http://jieitaisaiyou.web.fc2.com/tokusyu.html |url=http://jieitaisaiyou.web.fc2.com/tokusyu.html |script-title=ja:陸上自衛隊唯一の特殊部隊 特殊作戦群の解説 |language=ja |access-date=2012-11-28 |archive-date=2013-01-28 |url-status=dead }}</ref>
|-
|{{flag|Libya}}
| 
|align="center"| -
|align="center"| .40 S&W<br>.45 ACP
|-
|{{flag|Lithuania}}
|Lithuanian Armed Forces
|align="center"| -
|align="center"| 9mm
|align="center"|<ref>{{cite web|url=http://kariuomene.kam.lt/lt/ginkluote_ir_karine_technika/pistoletai/pistoletas_usp.html|title=Lietuvos kariuomenė :: Titulinis|work=kam.lt|access-date=2010-08-02|archive-url=https://web.archive.org/web/20100728132646/http://kariuomene.kam.lt/lt/ginkluote_ir_karine_technika/pistoletai/pistoletas_usp.html|archive-date=2010-07-28|url-status=live}}</ref>
|-
|{{flag|Luxembourg}}
|''Unité Spéciale de la Police'' of the Grand Ducal Police
|align="center"| -
|align="center"| -
|align="center"|<ref>{{cite web|url=http://www.usp.lu/armement-pistolets-fr.php |title=Unofficial Pistols Page, Equipment |website=Unité Spéciale de la Police |access-date=2009-10-06 |archive-url=https://web.archive.org/web/20110722161231/http://www.usp.lu/armement-pistolets-fr.php |archive-date=2011-07-22 }}</ref><ref>{{cite web|url=http://www.usp.lu/media/raids.pdf |title=L'Unite d'Intervention de la Police Luxembourgeoise |date=March 2006 |language=fr |publisher=RAIDS Magazine |access-date=2009-09-23 |url-status=dead |archive-url=https://web.archive.org/web/20110722160041/http://www.usp.lu/media/raids.pdf |archive-date=2011-07-22 }}</ref><ref>{{cite web|url=http://www.usp.lu/media/armas.pdf |title=UPS Unidad Especial de la Policia Luxembourguesa |author=Lasterra, Juan Pablo |year=2004 |language=es |publisher=ARMAS Magazine |access-date=2009-09-23 |url-status=dead |archive-url=https://web.archive.org/web/20110722161849/http://www.usp.lu/media/armas.pdf |archive-date=2011-07-22 }}</ref>
|-
|{{flag|Malaysia}}
|''Pasukan Gerakan Khas'' (PGK) of the Royal Malaysia Police
|align="center"| USP Compact<br>USP Tactical SD
| align="center" | 9mm
|align="center"|<ref>{{cite web |url=http://www.tactical-life.com/online/special-weapons/malaysian-special-forces |title=Malaysian Special Forces |author=Thompson, Leroy |date=December 2008 |publisher=Special Weapons |access-date=2009-12-14 |archive-url=https://web.archive.org/web/20120402013858/http://www.tactical-life.com/online/special-weapons/malaysian-special-forces/ |archive-date=2012-04-02 |url-status=live }}</ref>
|-
|{{Flag|Norway}}
|''Forsvarets Spesialkommando''
|
|
|<ref>{{Cite web|date=2021-04-03|title=POTD: Norwegian Special Operation Commandos (FSK)|url=https://www.thefirearmblog.com/blog/2021/04/03/potd-norwegian-special-operation-commandos/|access-date=2021-04-04|website=The Firearm Blog|language=en-US}}</ref>
|-
|{{flag|Poland}}
|''Grupa Reagowania Operacyjno-Manewrowego'' (GROM) of the Polish Special Forces
|align="center"| USP family
|align="center"| -
|align="center"|<ref>{{cite web|url=http://www.grom.mil.pl/uzbrojenie_pliki/UZBROJENIE.HTM|title=//- Strona poświęcona Wojskowej Formacji Specjalnej GROM -//|work=grom.mil.pl|access-date=2011-08-06|archive-url=https://web.archive.org/web/20110814155936/http://www.grom.mil.pl/uzbrojenie_pliki/UZBROJENIE.HTM|archive-date=2011-08-14|url-status=dead}}</ref>
|-
|{{flag|Portugal}}
|{{wipe|Portuguese Air Force}}
| align="center" | USP family
| align="center" | 9mm
| align="center" |<ref name="Portuguese air force">{{cite web|url=http://www.operacional.pt/afeganistao-unidade-de-proteccao-da-forca-em-operacoes/|title=AFEGANISTÃO: UNIDADE DE PROTECÇÃO DA FORÇA EM OPERAÇÕES - Operacional|work=operacional.pt|access-date=2010-08-30|archive-url=https://web.archive.org/web/20150724022532/http://www.operacional.pt/afeganistao-unidade-de-proteccao-da-forca-em-operacoes/|archive-date=2015-07-24|url-status=dead}}</ref>
|-
|{{flag|Serbia}}
|Special Brigade
|align="center"| USP
|align="center"| 9mm
|align="center"|<ref>{{cite web|url=http://specijalne-jedinice.com/Oprema/Pistolji/HK-USP.html|title=Specijalne-jedinice.com - HK-USP|website=specijalne-jedinice.com|access-date=2017-01-25|archive-url=https://web.archive.org/web/20170202075401/http://specijalne-jedinice.com/Oprema/Pistolji/HK-USP.html|archive-date=2017-02-02|url-status=dead}}</ref>
|-
|{{flag|Singapore}}
|Special Operations Command of the Singapore Police Force
| align="center" | USP Compact
|align="center"| -
|align="center"|<ref>{{cite web|url=http://spf.gov.sg/prints/plm/2005/may05_pg01.htm|archive-url=https://web.archive.org/web/20070714230234/http://spf.gov.sg/prints/plm/2005/may05_pg01.htm|title=Singapore Police Force - Police Life Monthly|archive-date=14 July 2007|work=spf.gov.sg}}</ref>
|-
|{{flag|South Africa}}
|South African Police Service Special Task Force
|align="center"| USP<br>USP Compact
|align="center"| 9mm
|align="center"|<ref>{{cite web|url=http://www.sapstf.org/Equipment.aspx|title=Taakmag|work=sapstf.org|access-date=2012-08-11|archive-url=https://web.archive.org/web/20141216182301/http://www.sapstf.org/Equipment.aspx|archive-date=2014-12-16|url-status=dead}}</ref>
|-
| rowspan="4" |{{flag|Spain}}
|Spanish Armed Forces
|align="center"| -
|align="center"| -
|align="center"|<ref name="kemp2008"/>
|-
|''Grupo Especial de Operaciones'' (GEO) of the ''Cuerpo Nacional de Policía''
|align="center"| USP Compact
|align="center"| -
|align="center"|<ref>{{cite web |url=http://www.policia.es/geo/material.htm?reload_coolmenus |title=Web Del Grupo Especial De Operaciones (GEO) |language=es |publisher=Spanish National Police Corps |access-date=2010-06-11 |url-status=dead |archive-url=https://web.archive.org/web/20090606025613/http://www.policia.es/geo/material.htm?reload_coolmenus |archive-date=2009-06-06 }}</ref>
|-
|''Guardia Civil''
|align="center"| USP Compact
|align="center"| -
|align="center"|<ref>{{cite web |url=http://www.guardiacivil.org/revista/766/articulo_1.pdf |title=Novedad en Armas Cortas |date=February 2008 |language=es |publisher=Guardia Civil |access-date=2010-01-13 |url-status=dead |archive-url=https://web.archive.org/web/20110916094701/http://www.guardiacivil.org/revista/766/articulo_1.pdf |archive-date=2011-09-16 }}</ref>
|-
|{{flag|Basque Country||}} ▶ Ertzaintza
|align="center"|USP Compact
|align="center"| 9&nbsp;mm
|align="center"| <ref>{{cite web|url=https://www.erne.es/Web/Modulos/Medio/Medio.aspx?Cod=293 | title=ErNe Basque Police syndicate website|access-date=2020-07-01}}</ref>
|-
|{{flag|Ukraine}}
|Special Group "Alpha" of the Security Service of Ukraine
|align="center"| USP
|align="center"| 9&nbsp;mm
|align="center"|<ref>{{cite web|url=http://www.bratishka.ru/archiv/2009/6/2009_6_7.php | title=Профессионалы: Украинская "Альфа": терроризм не пройдет|url-status=dead |archive-url=https://web.archive.org/web/20150923220836/http://www.bratishka.ru/archiv/2009/6/2009_6_7.php |archive-date=2015-09-23}}</ref>
|-
| rowspan="3" |{{flag|United States}}
|Federal Flight Deck Officer (FFDO's)
|align="center"| USP40c/LEM
|align="center"| .40S&W
|align="center"|<ref>{{cite web|url=http://hk-usa.com/heckler-koch-defense-wins-transportation-security-administration-pistol-contract|title=Heckler & Koch Defense Wins Transportation Security Administration Pistol Contract|work=Heckler & Koch|access-date=2015-06-15|archive-url=https://web.archive.org/web/20150907215142/http://hk-usa.com/heckler-koch-defense-wins-transportation-security-administration-pistol-contract/|archive-date=2015-09-07|url-status=dead}}</ref>
|-
|Maine State Police
|align="center"| USP45
|align="center"| .45 ACP
|align="center"|<ref>{{cite web|url= http://www.maine.gov/dps/msp/about/history|title=State Police: Maine State Police History|work=maine.gov|access-date=2021-04-06|archive-url=https://web.archive.org/web/20210406060438/http://www.maine.gov/dps/msp/about/history|archive-date=2021-04-06|url-status=live}}</ref>
|-
|Santa Monica Police Department in California
|align="center"| USP45<br>USP9
|align="center"| .45 ACP<br>9mm
|align="center"|<ref>{{Cite web |url=http://www.seanegen.net/attachments/File/Combat%20Tactics%20Samples/CTS08_SMPD_final.pdf |title=Archived copy |access-date=2012-01-13 |archive-url=https://web.archive.org/web/20120610045038/http://www.seanegen.net/attachments/File/Combat%20Tactics%20Samples/CTS08_SMPD_final.pdf |archive-date=2012-06-10 |url-status=dead }}</ref>
|}

==References==
{{Reflist|30em}}

==Bibliography==
*{{cite book| last = Kokalis| first = Peter| year = 2001| title = Weapons Tests And Evaluations: The Best Of Soldier Of Fortune| publisher = Paladin Press| location = Boulder, Colorado, USA| isbn = 978-1-58160-122-0}}

==External links==
{{Commons and category|HK USP|HK USP}}
*[http://www.heckler-koch.de/HKWebText/detailProd/1925/135/4/21 Manufacturer's website]
*[https://web.archive.org/web/20110711172218/http://www.hk-usa.com/-images/shared/USP%20Manual%20REV%203-07.pdf Operator's manual]
*[https://web.archive.org/web/20090315134948/http://world.guns.ru/handguns/hg11-e.htm Modern Firearms]
*[https://archive.today/20130112181053/http://50ae.net/collection/usp45/ H&K USP .45 pictorial]


{{DEFAULTSORT:Heckler and Koch USP}}
[[Category:Police weapons]]

{{Sourceattribution|Heckler &amp; Koch USP|1}}