Heckler & Koch USP - Testing

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.

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.

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.