New Grenades

The Army has officially adopted the M111 (and it’s practice counterpart the M112).  May not sound terribly significant, but they are the first lethal hand grenades adopted since 1968.

As many know, our standard M67 grenade works pretty well as a fragmentation grenade. Pull the pin, four-ish seconds later it goes ‘splodey, and sends out shards of metal in pretty much every direction. Basic, simple stuff. Unless you have to use it indoors, within the blast radius of the fragments. Fragments can get deflected, go in odd directions, through thin walls – not as much fun, right?

“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 at the Capabilities Program Executive Ammunition and Energetics. “The risk of fratricide on the other side of the wall was too high.”

The M111 addresses that problem head-on. Blast overpressure radiates through enclosed space and cannot be stopped by interior walls the way fragmentation can, creating lethal effects that reach every corner of a room. The M67 is not going away, Morris said. In open terrain, soldiers will continue to use it to maximize lethal fragment effects. The two grenades are designed to complement each other.

Probably my favorite paragraph from the article follows:

The M111 formally replaces the Mk3A2 offensive hand grenade, a concussion-type weapon that entered service alongside the M67 in 1968. Unlike the M67, which remains in the active inventory, the Mk3A2 was long ago restricted from use because its body contains asbestos. The M111 uses a plastic body that is fully consumed during detonation, eliminating the health hazard.

Has there ever been a case of mesothelioma reported in someone sharing a room with an exploding grenade? (“Call Dewey, Cheatham, and Howe for action!”)

Okay, I know, walking into a cloud of asbestos particles to confirm cleared rooms repeatedly won’t do anyone any good… but it still sounds like an odd worry.

Back to the M-67, it replaced the M-33 and M-26  predecessors and has been in constant use since 1968, an eternity in weaponry terms.

Its steel body contains 6.5 ounces of Composition B explosive, a mixture of RDX and TNT. It has a lethal radius of 5 meters, a casualty-producing radius of 15 meters and fragments capable of reaching 230 meters. In more than 55 years of continuous service it has been used in every major American conflict from Southeast Asia through Afghanistan and Iraq.

230 meters? Yeah, that sheet rock wall is not going to provide much peace of mind. At least the training curve should be short – the M-111 uses the same 5 step arming process, so in theory any trained soldier can use one or the other without having to remember which is which.

This was a lesson the Russians learned over forty years ago, and they adopted different grenades in the mid ’80s.

The RGN offensive grenade kept the fragmentation radius limited, protecting the assaulting soldier. The RGO defensive grenade was built to saturate open ground with fragments from a covered position. Both used the same dual-function fuze that could detonate on contact or trigger automatically at four seconds, eliminating the delay problem entirely. Military.com

Note the M-111 supplements the M-67, not replaces it. Think of them as – well, using your indoor voice or your outdoor voice. Indoor grenades vs. outdoor grenades.

Category: Army, Science and Technology