The Heckler & Koch GMG ("GranatMaschinenWaffe" or "GraMaWa") is a 40mm automatic grenade launcher similar in form and function to the American Mk 19 series. It fires a high-velocity 40x53mm grenade in various warhead types to suit mission requirements. The high-velocity form contrasts the 40x46mm low-velocity series found in several shoulder-fired weapons. The high-velocity version is primarily reserved for vehicle-mounted guns. As such, the GMG is an oversized automatic grenade projector usually fitted to a heavy duty pintle mounting or tripod assembly.
Overall dimensions include a running length of 1,090mm with a barrel of 415mm long. The field version of the weapon consists of the 29kg gun system and 11kg tripod. The automatic nature of the weapon utilizes a recoil-based API (Advanced Primer Ignition) blowback action consistent with cannon caliber types 20mm and larger. Through the API action, the primer is ignited while the bolt is still in motion (moving forward) during which the cartridge is still being seated into the chamber. The bolt moves both forward and backward in the action, allowing for a reduced recoil force to be achieved which serves an automatic weapon such as this very well. The GMG can achieve a rate-of-fire of 350 rounds per minute and fires each grenade at a muzzle velocity of 790 feet per second out to an effective range of 1,500 meters and maximum engagement range of 2,200 meters. The GMG is fed by a 32-round disintegrating link belt usually held in an accompanying ammunition box. Feeding is through the right side of the receiver with spent casings ejected through a port on the left side. A carrying handle is fitted at the base of the barrel while additional aiming handles are present at the rear of the receiver. The barrel is capped by a long slotted muzzle brake. While fitted with standard iron sights, a reflex optical sight is also provided.
The GMG was designed by engineers at Heckler & Koch from 1992 to 1995 before seeing adoption by German Army forces in 1996. The series continues production today (2013) and is in the inventories of Canada (as the licensed-produced Rheinmetall-Canada "C16 CASW"), Finland (as the "40 KRKK 2005"), Greece, Ireland, Latvia, Lithuania, Netherlands, New Zealand, Norway, Poland, Portugal, Slovenia, the United Kingdom (as the "L134A1") and the United States (under SOCOM).
Canada; Finland; Germany; Greece; Ireland; Latvia; Lithuania; Malaysia; Netherlands; New Zealand; Norway; Poland; Portugal; Slovenia; United Kingdom; United States
(OPERATORS list includes past, present, and future operators when applicable)
Capable of suppressing enemy elements at range through direct or in-direct fire.
Qualities of this weapon have shown its value to Special Forces elements requiring a versatile, reliable solution for the rigors of special assignments.
1,090 mm 42.91 in
415 mm 16.34 in
104.72 lb 47.50 kg
Iron; Optional Optics.
API Blowback; Automatic
Gas pressure from the rearward movement of the ignited cartridge case provides the needed bolt movement, ejecting the spent case and stripping a fresh case from the magazine.
(Material presented above is for historical and entertainment value and should not be construed as usable for hardware restoration, maintenance, or general operation - always consult official manufacturer sources for such information)
Rounds / Feed
32-round disintegrating belt
*May not represent an exhuastive list; calibers are model-specific dependent, always consult official manufacturer sources. **Graphics not to actual size; not all cartridges may be represented visually; graphics intended for general reference only.
5,000 ft (1,524 m | 1,667 yd)
790 ft/sec (241 m/sec)
Granatmaschinengewehr (GMW / GraMaWa) - Base Series Designation.
C16 CASW ("Close Area Suppression Weapon") - Canadian Army designation.
40 KRKK 2005 - Finnish Army designation
L134A1 - British Army designation
Ribbon graphics not necessarily indicative of actual historical campaign ribbons. Ribbons are clickable to their respective campaigns / operations.
The "Military Factory" name and MilitaryFactory.com logo are registered ® U.S. trademarks protected by all applicable domestic and international intellectual property laws. All written content, illustrations, and photography are unique to this website (unless where indicated) and not for reuse/reproduction in any form. Material presented throughout this website is for historical and entertainment value only and should not to be construed as usable for hardware restoration, maintenance, or general operation. We do not sell any of the items showcased on this site. Please direct all other inquiries to militaryfactory AT gmail.com.
Part of a network of sites that includes GlobalFirepower, a data-driven property used in ranking the top military powers of the world, WDMMA.org, the World Directory of Modern Military Aircraft, and SR71blackbird.org, detailing the history of the world's most iconic spyplane.