HK121
Heckler & Koch GmbH · Machine Gun · In Production · 2011
Also known as: MG5, HK MG5
Overview
The HK121 is a gas-operated, belt-fed general-purpose machine gun developed by Heckler & Koch and chambered in 7.62x51mm NATO. Introduced in 2011, it uses a rotating-bolt, open-bolt action firing from a disintegrating belt, with a quick-change barrel, adjustable gas regulator, folding bipod, and collapsible stock. Adopted by the German Army as the MG5 to succeed the Cold War-era MG3, it can be deployed in light infantry, coaxial, and vehicle-mounted roles with an effective range of roughly 1,000 meters.
Specifications
| Weight (empty) | 10800 g (381.0 oz) |
| Overall Length | 1165 mm (45.87") |
| Barrel Length | 550 mm (21.65") |
| Action Type | Gas Operated |
| Firing Mechanism | Open Bolt |
| Trigger Type | Single Stage |
| Magazine Type | Belt |
| Muzzle Velocity | 810 m/s (2657 fps) |
| Muzzle Energy | 3116 J (2298 ft·lbf) |
| Effective Range | 1000 m (1094 yd) |
| Maximum Range | 3500 m (3828 yd) |
| Rate of Fire | 700 rpm |
| Barrel Rifling | Right Hand |
| Number of Grooves | 4 |
| Frame Material | Steel |
| Barrel Material | Steel |
| Stock Material | Polymer |
| Finish | Phosphate |
Calibers
- 7.62x51mm NATO · primary · 7.62x51mm NATO — also known as .308 Winchester, 7.62mm NATO
Features
- Firing modes: Full Automatic
- Feed systems: Disintegrating Belt
- Safety mechanisms: Manual Safety
- Features: Quick Change Barrel, Adjustable Gas Regulator, Rotating Bolt, Picatinny Rail, Folding Bipod, Collapsible Stock, Ambidextrous Controls
Variants
Service history
Operators
- German Army · adopted 2015 · as MG5
Production
Production years: 2011-present
German Bundeswehr placed an initial procurement order of roughly 7,114 units as the MG5.
Origin
Country of origin: Germany
Designer: Heckler & Koch
Notes
Fires fully automatic only, fed by 50- or 120-round disintegrating DM60/M13-type belts. The selectable gas regulator allows the cyclic rate to be set between roughly 640 and 800 rounds per minute. Issued in multiple barrel-length variants (MG5, MG5A1, MG5A2, MG5S) for different mission profiles.
Background
Developed as the modern successor to the legendary MG3 (itself descended from the WWII-era MG42), the HK121 was Heckler & Koch's answer to NATO's need for a lighter, more controllable 7.62mm general-purpose machine gun. After extensive trials it was adopted by the Bundeswehr under the designation MG5.