US Army Approves M111, Its First New Lethal Grenade Since 1968

Designed for close-quarters fighting, the M111 uses blast overpressure instead of fragmentation.

Soldier of Fortune

For the first time in more than half a century, the U.S. Army has approved a new lethal hand grenade for service.

The weapon is the M111 Offensive Hand Grenade (OHG), now cleared for Full Material Release (FMR), allowing the Army to begin fielding it to operational units.

The M111 replaces the aging Mk3A2 offensive grenade, marking the first new lethal hand grenade to achieve FMR since 1968. The Mk3A2 has been increasingly restricted in use because its body contains asbestos, whereas the M111 uses a plastic body that is completely consumed during detonation.

The grenade was developed by the Army’s Close Combat Systems program in cooperation with engineers at the DEVCOM Armaments Center at Picatinny Arsenal, and is designed specifically for close-quarters fighting in enclosed and restricted environments.

The M111 will improve readiness while giving soldiers a safer option for fighting in buildings and other confined spaces, the Army says.

“One of the key lessons learned from the door-to-door urban fighting in Iraq was that the M67 grenade wasn’t always the right tool for the job,” said Col. Vince Morris, project manager for Close Combat Systems. “The risk of fratricide on the other side of the wall was too high.”

The new grenade is designed to fight more effectively in close quarters by using blast overpressure (BOP) rather than fragmentation.

A grenade utilizing BOP “can clear a room of enemy combatants quickly, leaving nowhere to hide while ensuring the safety of friendly forces,” Morris said.

When used in grenades, blast overpressure delivers devastating effects against enemy personnel and equipment without projecting fragments, giving soldiers a potent option in confined terrain.

In open terrain, soldiers will continue to rely on the M67 fragmentation grenade to maximize lethal fragment effects, whereas in enclosed and restricted spaces they can employ the M111.

“We’ve given our Soldiers and joint warfighters the flexibility to determine in the field which type of grenade will best suit the situation they are facing, whether in open terrain or confined areas,” said Tiffany Cheng, an engineer who worked on developing the M111 at Picatinny Arsenal.

The new grenade and its training version, the M112, use the same five-step arming process as the M67 fragmentation grenade and its training counterpart, the M69.

The M111 and M112 use the same fuze family as the M67 and M69 respectively, helping simplify training and production.

The approval of the M111 marks a rare moment in the evolution of U.S. hand grenades. The last time the Army introduced a new lethal grenade design was in 1968, when the Mk3A2 entered service.

More than five decades later, the battlefield has changed dramatically. Urban combat and operations inside complex structures have become common features of modern warfare, forcing armies to reconsider how small infantry weapons are used.

With the M111, the Army is betting that a blast-focused offensive grenade will give soldiers a safer and more effective option when combat shifts into enclosed spaces.

– Based on material from Michael Chambers, Picatinny Arsenal.