In the world of military firearms, handguns are sidearms. They are the weapons soldiers turn to in special conditions and rarely issued. Sidearms are not necessarily defensive weapons, but they are certainly not primary weapons. You won’t lead a charge with a handgun or lay down suppressive fire with a sidearm; that’s not traditionally how sidearms work. However, HK designed the Mk 23 to be the world’s first offensive handgun.

I don’t mean offensive like sending college students to a safe space, but it is certainly triggering to terrorists and the enemies of democracy. What makes a handgun offensive? Well, the Mk 23 was designed to act as a primary weapon in limited roles for troops doing sneaky things in non-permissive places. To fully understand why the weapon worked, we have to understand how the weapon worked.

 

Into the Mk 23

The Mk 23 is an absolute unit of a pistol. It’s a massive 45 ACP pistol that contains 12 rounds of them 230-grain pills. The Mk 23 is 9.65 inches long with a suppressor and weighs 2.43 pounds empty. For comparison, the .429 Desert Eagle is 10.75 inches long. Mk 23 is a huge gun, but since it was designed for offensive use, there wasn’t a need for concealment by any means.

Mk 23
(Courtesy of HK)

This massive pistol is exceptionally easy to shoot due to its large size. It eats up recoil and muzzle rise just by being so massive. Additionally, the Mk 23 features a dual-recoil-spring design to help eat even more recoil up. SOCOM got ambidextrous controls, a DA/SA action, and a decocker that lowered the hammer silently.

Mk 23
(Courtesy of HK)

The Mk 23 utilized a European-style magazine release located on the trigger guard. While odd, it works very well, especially when using gloves. HK designed this system to be ambidextrous for quick reloads. Shooters could use their trigger finger or support hand thumb to release the magazine.

 

Keeping It Quiet

One requirement of the Offensive Handgun Weapon System was for a suppressor. Sadly, HK’s didn’t meet standards. SOCOM wanted a suppressor that shaved off 30 decibels from the muzzle blast. HK’s didn’t deliver. Knight Armament got the closest with their suppressor at a 28.8-decibel reduction. HK and Knight teamed up but faced some difficulty. The short-recoil design didn’t work well with a suppressor.

(Courtesy of HK)

This led to the development of a piston inside the suppressor that utilizes gas to ensure proper function with the Mk 23. The 45 ACP cartridge is naturally subsonic, so the supersonic crack was eliminated from the start. With a suppressor added, the weapon was absurdly silent. Early prototypes featured a slide lock that would prevent the slide from cycling when the weapon fired.

The idea was to eliminate the noise of the slide slamming back and forth. However, this was found to prematurely wear the slides. SOCOM abandoned the feature, and it was regulated to just a few prototypes.

 

Through the Ringer

HK’s Mk 23 is one of the most tested handguns ever conceived. SOCOM treated it like a red-headed stepchild and abused it thoroughly. This included extremely strict reliability testing, and in fact, it’s widely considered that Mk 23 underwent the strictest testing ever for a handgun. The requirement was for 2,000 MRBF (Mean Rounds Before Failure). The HK Mk23 blew this requirement out of the water and delivered an impressive 6,027. After 20,000 rounds only an O-ring needed replacement.

The gun went through saltwater testing, mud, sand, and more. SOCOM tried to do everything possible to destroy this gun. Yet, it persevered, and in 1996 the pistol was delivered to special operation units. Now that we’ve identified what the Mk 23 is let’s talk about its role.

 

In Combat

Special Ops personnel used the weapon to offensively eliminate sentries and personnel that prevented infiltration. Users could take down dogs, guards, and similar folks without alerting the area to the operation. The very low recoil and muzzle rise allowed the weapon to be incredibly easy to handle compared to standard handguns.

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SEAL with Mk 23 (DoD)

As such, it was a better fighting tool than the sidearms on the market. Spec Ops personnel could use it as a primary weapon without being undergunned at typical handgun ranges. The presence of an IR laser-aiming module allowed easy use with night vision. The Mk 23 acted as a metaphorical Death’s scythe at night. Under night vision, the weapon allowed the user to take down a bad guy without the subject ever knowing what happened.

The Mk 23 was admittedly a short-lived concept. Once the Global War on Terror kicked off, it was all about rifles, and the Offensive Handgun was never needed. It was a concept for a more conventional war. Even so, the Mk 23 is still produced for the civilian market. Shooters who are willing to pay a premium can get their Mark 23 model with just a few differences, namely the markings.

Does anyone in the audience have experience with the Mk23? If so, let us know what you think in the comments below!

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