In August, 1991 a request was made for the U.S. Special Operations Command (USSOCOM) for an "offensive" handgun. Termed the OHWS, for Offensive Handgun Weapon System, it was a pistol designed within certain specified parameters that would be sufficient for conducting "offensive" operations, as opposed to the more tradtional role for the handgun, for "defensive" operations.  HK and Colt were chosen to compete against each other for the new pistol.  HK eventually won out, and the contract was awarded to them.  It has undergone many changes from its birth in 1991.  Some are obvious, some are not.  The official name for the pistol is Mark 23, Mod 0.  Not very catchy.  That is why it is more popularly known as the SOCOM.  
HK Mk. 23 Mod 0 Special Operations COMmand pistol
       
  The handgun is based on HK's successful USP Tactical design, being slightly larger and heavier. Mk.23 is a recoil operated, locked breech handgun that utilized modified Browning-style locking wia extraction port. Trigger is Double-Action with safety and decocker levers. Barrel is threaded to accept silencers (manufactured for US Govt. by Knight's Manufacturing, USA). Frame is made from high strenght polymer with stell inserts, under the barrel frame has integral rails for mounting different laser aiming devices and tactical flashlights. Sights are dovetailed and ajustable. The gun is quite heavy, and some US SpecOps units preferred to use HK's USP Tactical instead of Mk.23, mostly due to USPs' smaller size and weight.

-(Shortened and/or modified version of the article at world.guns.ru).

 
Mk. 23 unloaded with a laser sight and Knight's silencer
 
Mk. 23 with Knight's silencer
Mk. 23 with Knight's silencer and a tactical flash light

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H&K USP .45 (Universelle Selbstlade Pistole)
  GAME DATA: Mk. 23

The Mk. 23 is a large and noisy companion, but with wide variety on accessories and 12 rounds of .45 ACP it has lots of tactical value and stopping power.
Used by elite Prometheus troops and US Marines.

   
Name: Mk. 23  
Slot: 2, pistols  
Caliber: .45 ACP  
Capacity: 12 rounds  
Firemodes: Semi-auto  
Accuracy: Fair  
Other: Laser sigth or tactical light  
   
   
  GAME DATA: Mk. 23 SD

The silenced version will serve well in night operation and mission requiering stealth.

   
Name: Silenced Mk. 23  
Slot: 2, pistols  
Caliber: .45 ACP  
Capacity: 12 rounds  
Firemodes: Semi-auto  
Accuracy: Fair  
Other: Silencer and laser sigth or tactical light  
   
   

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