Offensive Handgun Weapons System—Special Operations Peculiar


Spec Ops

US Operated


  • Caliber .45 ACP
  • Overall Length 9.65in (245mm)
  • Action SA/DA
  • Capacity 12 rounds
  • Barrel Length 5.87in (149mm)
  • Height 5.90in (150mm)
  • Weight (empty) 2.66lb (1.21kg)
One of the most thoroughly tested handguns in history. The first caliber .45 ACP pistol to enter U.S. military service since the M1911.


The HK MK 23 is a one of the most well known handguns due to its introduction from special operations. This is one of the only handguns specifically designed for special operations units that is an offensive firearm rather than a secondary defense firearm. It was chosen from a competition by USSOCOM to become the Special Operations official “Offensive Handgun Weapons System”.

Winner of the OHWS Competition

One of the defining features of the HK Mk 23 is the ability attach various attachments that special operations soldiers would take plenty advantage of in the field. It is known to be one of the first to come equipped with barrel threads for a suppressor and a rail for a laser aiming module for precise accuracy.

The HK Mk 23 is chambered in .45 ACP for effective offense stopping power with a high capacity magazine holding 12 rounds. This almost matches the capacity count of rounds in the standard US military handgun, the Beretta M9, while having the larger round of the previous standard US military handgun, the Colt M1911.

HK MK23 Showcase
Heckler & Koch MK23 w/ Accessories

Hk Mk 23 Development

The Hk Mk 23 was born from a need to have an offense handgun as a primary weapon in close quarters. This was issued from the United States Special Operations Command (USSOCOM) in 1989. The OHWS Competition ended in June 1995 with Heckler & Koch winning the contract. The only other submission in the OHWS Competition was the Colt OHWS.

The Hk Mk23 is an extremely well made and reliable handgun. It is touted for being one of the most tested handguns in history. It is completely ambidextrous allowing shooters of all types to handle it effectively. The Hk Mk23 is also waterproof and corrosion resistant. One of the features that it has over the Colt OHWS is the fact that it is manufactured to handle high pressure .45 ACP +P and .45 Super ammo without modifications. This was a requirement of the OHWS Competition.

Mk 23 Use and Reception

In 1996, the MK23 was manufactured and delivered to SOCOM. The reception was mixed with many Special Operations units. This was because of the handgun’s size and not necessarily the performance or reliability.

The MK23 was issued with a Knight’s suppressor and a special issue Laser Aiming Module. This put this already large handgun at a staggering size in the hands of soldiers in the field. Even though it is issued as an offense handgun, the practical use of this firearm became mute because of it’s size even though it was extremely accurate and reliable.

SOCOM unites eventually opted for other handguns and/or other smaller carbines to handle the offense role.

MK23 versions and Alternatives

There were no different official released versions of the HK MK23. Due to the criticisms of the initial release, HK developed a smaller version of the offense handgun: the HK USP Tactical.

The USP was a more widely received handgun than the MK23. It is smaller handgun with very similar functionality as the MK23. This was an improvement to help with mobility on the battlefield.

Civilian Life

The civilian issued Mk23 handgun called the Mark 23, was sold not long after the Mk23 was delivered to military units. Due to the size, the Mark 23 became more of an expensive novelty rather than a practical home defense handgun.

The popularity increased due to its presence in movies and video games including a game called Metal Gear Solid. Because of this popularity, and craftsmanship, the price of the Mark 23 is quite high. Much higher than other handguns of similar caliber.

Today, HK has made more current and up to date variations of Mk23. If you are looking for a more practical alternative, HK has produced similar handguns like the USP, HK45, and the P30. The MK23 and the Mark 23 have turned into more of a collector’s item today.

Weapon Variations



  • Caliber .45ACP
  • Overall Length 9.65 in.
  • Barrel length 5.87 in.
  • Capacity 12 rounds
  • Action SA/DA
  • Weight (empty) 2.43 lb


  • Caliber .45ACP
  • Overall Length 8.03 in.
  • Barrel length 4.4 in
  • Capacity 10 rounds
  • Action SA/DA
  • Weight (empty) 1.71 lb


  • Caliber 9x19mm
  • Overall Length 7.71 in.
  • Barrel length 4.45 in.
  • Capacity 15 rounds
  • Action SA/DA
  • Weight (empty) 1.51 lb