Heckler & Koch MARK23
The Heckler & Koch MK 23, MK 23 MOD 0, Mark 23, or USSOCOM MARK 23, is a semi-automatic large-frame pistol chambered in .45 ACP. designed specifically to be an offensive pistol. The USSOCOM version of the MK23 came paired with a laser aiming module(LAM), and suppressor. The USSOCOM MK23 was adopted by the United States Special Operations Command (USSOCOM) for special operations units beating out the nearest competitor, Colt's OHWS. Development of the pistol began in 1991 as special operations representatives identified the need for an "Offensive Handgun Weapons System—Special Operations Peculiar", and delivery of the pistol's began in May 1996 to the special operation units.
While the USSOCOM MK23 designation usually applies to the complete system, it is also commonly used in reference to the pistol component alone. The LAM and suppressor were developed by Insight Technology and Knight's Armament Company (KAC), respectively. The civilian version of the Mk23 sold by itself is designated the Mark 23.
The MK 23 is considered a match grade pistol, and is capable of making a 2-inch (51 mm) group at 25 metres (27 yd). The MK 23 is designed for exceptional durability in harsh environments, being waterproof and corrosion-resistant. It uses a polygonal barreldesign, which is reported to improve accuracy and durability, being much more expensive to produce. It also features an ambidextrous safety and magazine release on both sides of the frame. The magazine release is at the rear edge of the trigger guard, which is wide enough to allow the use of gloves. A decocking lever is on the left side, which will silently lower the cocked hammer. The MK 23 is part of a larger weapon system that includes an attachable Laser Aiming Module (LAM), a suppressor, and some other features such as a special high-pressure match cartridge (.45 +P ammunition).
The firearm was tested and found to be capable of firing tens of thousands of rounds without a barrel change. It remains reliable in harsh conditions, making it suitable for use by special forces. The .45 ACP round has considerable stopping power and yet is subsonic, making it suitable for use with a suppressor.
Heckler & Koch has offered the MK 23 on the civilian market and law enforcement as the MARK 23. It is distributed by its subsidiaries HK Inc. (United States) and HKJS GmbH (Germany).
The models for the U.S. market initially came with a 10-round magazine, to comply with the U.S. Assault Weapons Ban. The ban has now expired, and the civilian Mark 23 comes with the same 12-round magazine as the government variants, except in a few states that enforce their own bans on magazines larger than 10 rounds. In Canada, the Mark 23 pistol is still supplied only with 10-round magazines, as per the 1995 Firearms Act.
According to the Operators Manual, there are few differences between the civilian Mark 23 and the government MK 23. These differences are the slide engraving "Mark 23" which is only for the first half of the first year of production in 1996 (KG date code), the roll-mark "MARK 23" which is for mid 1996 to now, these instead of "MK23 USSOCOM", Matte vs shiny finish for different civilian years, tan vs black frame (500 tan ones were made), and a barrel conforming to SAAMI headspace specifications for the military vs civilian made, as the military barrels were made to allow ball ammunition to work more reliably.