Heckler & Koch USP: heckler koch 45 usp, heckler and koch usp 40, heckler koch compact usp 45

The Heckler & Koch USP (Universelle Selbstladepistole, or "Universal Self-loading Pistol") is a semi-automatic pistol designed by the German arms manufacturer Heckler & Koch.

Design details

When Heckler & Koch introduced the USP in 1993^[2], it marked the first time HK chose to incorporate many traditional handgun design elements, such as those of John Browning's M1911, in one pistol.^[3] Two principles guided its development — the first being the use of molded polymer material, and the second being the creation of a "pistol paradigm".

Heckler & Koch observed the strong points of its previous successful pistols for insight in developing "the best" pistol. Previous HK pistol innovations include the unique squeeze cocking mechanism of the Heckler & Koch P7, the precise roller-locked bolt of the Heckler & Koch P9S, and the double action-only system used by the VP70Z. In contrast to these ambitious designs, the USP uses a Browning linkless-locked breech action, similar to that developed by John Browning for use in the Browning P35 "Hi Power" pistol.^[4]^[5] The pistol also features a safety which allows it to be safely carried "cocked and locked".

The USP was originally built around the .40 S&W cartridge^[2], but a 9x19mm Parabellum was introduced at the same time. In May 1995, Heckler & Koch introduced a .45 ACP variant.^[6] The USP Compact series was introduced in 1996^[7] and is available in 9 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.

One of the most significant features of the USP is the mechanical recoil reduction system. This system is incorporated into the recoil/buffer spring assembly, located below the barrel. Designed primarily to buffer the slide and barrel and reduce recoil effects on the pistol components, the system also lowers the recoil forces felt by the shooter. The USP recoil reduction system is insensitive to ammunition types and does not require adjustment or maintenance. It functions effectively in all USP models.^[3] Using this same recoil reduction system, one of the related HK MK23 .45 ACP Special Operations Pistols fired more than 30,000 +P cartridges and 6,000 proof loads without damage to any major components. Abuse and function-testing of USPs have seen more than 24,000 rounds fired without a component failure.

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" nitride finish.^[3] Internal metal parts, such as springs, are coated with a Dow Corning anti-corrosion chemical to reduce friction and wear.^[7]^[8]

The USP was developed alongside the Mk 23 Mod 0, a .45 ACP handgun designed by Heckler & Koch for the USSOCOM. The frame and slide of the USP45 are slightly larger than those found on the USP40 and USP9, much like the Mk 23. The prominent oversized trigger guard allows the use of gloves when firing.^[3]

Variants

One of the remarkable 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).^[3]^[5]

By using a modular approach to the internal components,^[4] 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) modes and double-action only (DAO) modes.^[3]

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 well with the tapered magazine, making magazine changes faster due to lack of user-assisted guiding. Finger recesses in the grip frame also aid in magazine removal. On 9 mm and .40 caliber USPs, magazines are constructed of polymer reinforced with stainless steel. Magazines on the USP .45 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 — 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.

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.^[9]

USP Compact

The first USP Compact models appeared in 1994. These are scaled-down USPs, and are available in all the same cartridges as the full size version, and additionally the .357 SIG.^[1] 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. However, the USP Compact cannot be cocked from a dry-fired position as the hammer will be flush to the back of the slide.^{[dubious – discuss]} A spurred hammer, similar to the one that comes standard on the P10 can be installed onto the USP Compact. USP Compact models lack the mechanical recoil reduction system of the larger full sized USP pistols. Instead, a more compact recoil buffering system is composed of a polymer bushing, around the captive recoil spring, which is designed to absorb energy at the end of the slide's travel rearward. This polymer bushing, with an estimated lifespan of around 20,000 rounds, is used instead of the double spring/captive recoil spring/guide rod found in the full sized USP.

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 by a competent gunsmith the USP Compact effectively becomes a right or left-handed firearm with respect to the decocker and manual safety functions.

Heckler & Koch does not authorize caliber conversions, but a separate barrel for a .357 Sig or .40 S&W can be purchased from HK, or from companies like Midway USA or Jarvis, Inc. EFK Fire Dragon[1], an Arizona based pistol accessories company produces conversion barrels for both Full Size and Compact USP models. These conversion barrels can convert a .40 S&W to .357 Sig, and vice versa. They also manufacture 9mm conversion barrels. These 9mm conversion barrels can convert a 40/357Sig to a 9mm, but not a 9mm to a .40/.357 Sig. Also, a more powerful recoil spring may be need for a .357 Sig conversion as the .357 Sig operates at a higher PSI. Heckler & Koch currently does not make the Full Size USP in .357 Sig, making the .357 Sig conversion for the Full Size .40 S&W a highly desirable addition.

USP Compact Tactical

The USP45CT is a highly modified USP45C developed for use by U.S. special operations forces. Termed the CT for counter-terrorist by insiders, the HK USP45 Compact Tactical combines the proven features of the full-size USP45 Tactical pistol in a smaller, more concealable package.

USP Tactical

The USP Tactical (9mm Para, .40S&W, .45 ACP) incorporates a fully adjustable rear sight, a higher-profile front sight (as to be visible above the suppressor), an extended threaded barrel and O-ring, a match grade trigger, and an adjustable trigger stop. Sound suppressors designed for the USP Tactical are available from Knight's Armament and Gemtech. A unique feature of the USP Tactical is that the barrel is left-hand threaded (counter-clockwise to tighten), which makes the pistol incompatible with suppressors designed for the MK23 Mod 0. ^[10]

USP Expert

The USP Expert (9 mm Parabellum, .40 S&W, .45 ACP), was introduced in 1998^[12] and includes all the features of the Tactical, with the exception of the threaded barrel. The USP Expert also retains the USP match trigger. It also features an extended steel slide, which mostly hides the longer O-ring barrel and adds weight to help reduce muzzle flip and felt recoil even further. The expert has adjustable target sights similar to the USP Match, Elite, and Tactical, however the slide differs in that the rear sight seat has been milled lower^[12]. The Expert may be used with an extended magazine well, or jet funnel, in 9 mm and .40 S&W calibers, which is intended for use in conjunction with larger-capacity magazines. The Jet Funnel magazines are clear plastic and hold 18 rounds for 9mm, and 16 rounds for .40 S&W. The jet funnel magazine can be used without the jet funnel installed and will protrude slightly from the bottom of the magazine well. However, once the jet funnel is installed, only jet funnel magazines can be used. The standard USP magazines will not work as the funnel will impede them from fully inserting in the grip and locking into place.

USP Match

The USP Match (9 mm Parabellum, .40 S&W, .45 ACP) is specifically designed to appeal to target shooters. In addition to the features offered on the Expert, the Match distinguishes itself by its barrel weight, which replaces the elongated slide found on the Expert. The barrel weight provides counterbalance to the weapon's recoil, greatly improving follow up target tracking.^[13]

USP Elite

The USP Elite (9 mm Parabellum, .45 ACP) takes features found on the Tactical, Expert, and Match models, and combines them with a 6.02 in (153 mm) barrel and hand-fitted 9.45 in (240 mm) extended slide. The Elite also includes higher-profile fully adjustable front and rear sights.

Testing

As the USP was developed at the same time as the SOCOM MK23, the pistol underwent much of the same rigorous testing. The barrel is cold-forged from chromium steel for increased life. USP barrels post-1994 use a polygonal profile, whereas 1994 and earlier models utilize 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.^[14]

Temperature testing required the USP be frozen to −42 °C and fired, frozen again, and then be heated up to 67 °C and fired. These temperature tests were continually repeated with no adverse effects on the USP.^[14]

The gun was also subjected to NATO MIL-SPEC mud and rain tests, which were passed without difficulty. Water immersion and salt spray also presented no problems. German Navy combat divers have used the USP for two years without any signs of corrosion.

Safety testing exceeded the ANSI/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), hammer first, onto a steel backed concrete slab. 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, it was shown the recoil-reduction system reduces the force on the USP grip to approximately 300 newtons (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 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 much more subjective.

Service

The USP was adopted in Germany by the Bundeswehr (German armed forces) as the P8 in 1994^[15]. The P8 has only minor differences from the standard USP model, these being a reversed safety/decocker lever (on the P8, down indicates 'safe', and up indicates 'fire' — this is the opposite of the standard USP), and the 'S' and 'F' letters being printed onto the frame instead of onto the lever itself. The P8 has a traditional lands-and-grooves barrel instead of a polygonal barrel.^[16]

The P10, adopted by many German State Police forces, is in fact a USP Compact with the addition of a spurred hammer.^[17] Both P8 and P10 are chambered in 9x19mm Parabellum (9 mm NATO) only.^[16]^[17]

On August 24, 2004, SIGARMS 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.^[18] The HK pistol models chosen were the HK P2000 US, HK P2000 SK Subcompact, and the USP Compact/LEM (Law Enforcement Modification).^[19] The LEM trigger is basically 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, due to a lighter trigger pull (7.3–8.5 lbf) and shorter trigger reset than standard DAO trigger systems. The LEM trigger utilizes a two-piece "pre-cocked hammer" composed of a cocking piece and an external hammer. The hammer is pre-cocked when a round is chambered (slide is cycled). The LEM system supposedly also provides for more reliable primer ignition, since it utilizes a stronger hammer spring.

The LEM trigger can be installed on existing USP compact pistols that were purchased before the LEM trigger came on the market -- either by a certified gunsmith or by sending the pistol directly to Heckler & Koch. In addition, the USP compact pistol can retain its external safety even with the LEM trigger -- making it the only modified double-action pistol with an external safety for added peace of mind. The LEM USP compact pistol with external safety also appeals to M1911 aficionados who are trained to deactivate the safety while drawing.

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