SOCOM

Overview
The Mark 23 was the predecessor to Heckler & Koch's USP series of handguns. It is chambered for the popular .45 ACP cartridge and has a 12+1 round capacity. The SOCOM variant is a "weapon system" rather than just a pistol; the system includes the weapon itself, the AN/PEQ-6 Laser Aiming Module (LAM) manufactured by Insight Technology, and the large suppressor produced by Knight's Armament Company. Weapons manufactured for military use have "MK23 USSOCOM" engraved on the slide; total production the of SOCOM version was a little under 2,000 units. However, Heckler & Koch officially discontinued production of the Mark 23 in July of 2010.

It was built to conform to very stringent accuracy and reliability requirements set by the US SOCOM (Special Operations COMmand). While it met the accuracy and reliability goals, operators in the field despised the Mark 23 for its poor ergonomics, enormous size and heavy weight (the weapon is a foot and a half long with the suppressor fitted and the full system weighs five pounds, as much as an unloaded MP5 or three loaded 9mm Glocks); they tended to never be checked out, and most in SOCOM service spent peaceful careers sitting in armoury gun racks, ultimately being replaced by the smaller and lighter USP .45. American troops have nicknamed the MK 23 "The World's Only Crew-Served Pistol." A conversation with Nastasha Romanenko in the original Metal Gear Solid has her comment on this, saying that "some find it a little heavy and hard to use."

In Metal Gear Solid
The SOCOM is extremely accurate for a handgun, and reliable for taking out lone targets in short to middle range though is not very ideal to use against attack team units during a long-term engagement since it takes half a magazine to kill a enemy soldier in body armor. Single guards are easier to pick out though shots in the torso will not be as punishing. In earlier times of the game, the player will be forced to avoid using the SOCOM against lone or distant targets due to the loud noise it gives away unless a suppressor is found.

The SOCOM was used by Solid Snake during the Shadow Moses Incident, although at least one member of the Sons of Big Boss had a SOCOM on hand. During the Big Shell Incident, a SOCOM pistol was given to Raiden by Snake. In 2014, during the events of Liquid Ocelot's Insurrection, Raiden was in possession of a SOCOM.

The first gun found in Metal Gear Solid, it is often considered Snake's trademark gun, despite the fact that he does not once use it during Metal Gear Solid 2: Sons of Liberty. It can be completely missed fairly easily, though is available several times. If the player does not collect it, Snake automatically acquires it during a scripted sequence. A suppressor can be found in the Tank Hangar.

Snake finds another SOCOM pistol when revisiting Shadow Moses Island in Guns of the Patriots. Highlighting the nostalgia of the act, it is sitting under the same truck on the helipad from Metal Gear Solid that the SOCOM was originally in. If Snake points the gun, he remarks "just like old times," gaining one of the "nostalgia" Drebin Point bonuses. The SOCOM's suppressor is also found in the same room in the Tank Hangar.

Trivia

 * The SOCOM presented during the Shadow Moses Incident, Big Shell Incident and Liquid Ocelot's Insurrection was in fact the Phase II model handgun submitted for trials in the USSOCOM Offensive Handgun Weapon System (OHWS) competition around the later part of 1991, and not the actual production model of the Mk.23 Mod 0 (or Mark 23 - civilian version). The sound suppressor used, however, was the actual Knight's Armament Company model that was adopted for the weapon system. A picture of both the SOCOM and USP can be found in this old advertisement from Heckler & Koch.
 * The Mk 23 Mod 0 kit as issued by the US Navy included the Heckler & Koch Mk.23 handgun, two .45 ACP caliber twelve-round magazines, an AN/PEQ-6 (the Insight Technologies LAM-400 -- this LE Only model includes an IR illuminator and laser alongside a visible laser and light), and a Knight's Armament Corp. Mk23 .45 Cal. Sound Suppressor. Other accessories like holsters, magazine pouches, suppressor pouches, left handed LAM models, etc. were also available.

Gameplay
"An assault pistol developed at the request of U.S. Special Operations Command. It packs high knockdown power with its 45 caliber ammo, and its laser-aiming module and detachable suppressor give it the flexibility to excel in a wide variety of combat situations. The trigger mechanism is double action, but it can be carried around with the hammer in cocked and locked position, enabling the user to fire with precision on the very first shot. Holds 12 rounds."

- MK23 description in Metal Gear Solid: Portable Ops Plus

Appearances

 * Metal Gear Solid
 * Metal Gear Solid 2
 * Metal Gear Solid 4
 * Metal Gear Ac!d
 * Metal Gear Solid: Portable Ops Plus
 * Super Smash Bros. Brawl (Cannot be used, only seen in its holster)