Here's how Marine Corps mortar crews get explosive rounds to fall right on top of an enemy over 1,000 meters away

US Marine Corps/Lance Cpl. Robert KuehnUS Marines with 2nd Battalion, 1st Marine Regiment, 1st Marine Division, fire an M224 60 mm mortar system for a live-fire range during Exercise Iron Fist 2020 on Marine Corps Base Camp Pendleton, California.
  • Mortar crews can drop explosive rounds on enemies at great distances, keeping bigger threats like light armour at bay for other Marines moving on the battlefield.
  • But getting the round there is no easy task.
  • During a recent visit to Marine Corps Base Camp Pendleton for exercise Iron Fist, Insider had the opportunity to observe and learn how 60 mm mortar teams get rounds down range.
  • Visit Business Insider’s homepage for more stories.

CAMP PENDLETON, California – US Marine Corps 60 mm mortar teams can drop explosive rounds on their enemies from over 1,000 meters away, and Insider recently had the opportunity to watch them do it.

During a visit to Marine Corps Base Camp Pendleton, Insider observed a mortar crew firing off multiple rounds using an M224 60 mm light mortar, which is a high-angle-of-fire weapon that can be drop- or trigger-fired.

The training was carried out as part of the latest iteration of Iron Fist, an exercise that involves various training evolutions leading up to a large amphibious assault.

Cpl. Kevin Rodriguez, an experienced mortarman who said he chose the mortar because he wanted to follow in his grandfather’s footsteps, walked Insider through the ins and outs of firing a mortar and what it takes.


60 mm mortars are typically handled by a crew of Marines.

Ryan Pickrell/Business InsiderA Marine mortarman with the 2nd Battalion, 1st Marine Regiment, 1st Marine Division sets his target in his sights before firing.

Mortar crews have a gunner, an assisting gunner (squad leader), and an ammunition man. The crew is often supported by a forward observer and a fire direction centre.

When they’re on the move, the three main crew members divide the weapon components, like the gun, the bipod, the sight, and the baseplate, among themselves with no one person carrying the entire weapon.

A crew can set up or tear down a mortar in two minutes.

In combat, the team works together to put fire down range. Standard operating procedure is that the fire direction centre first passes range data to the gunner, who puts that into the sight and manipulates the weapon accordingly.

The ammo bearer then hands a prepared round to the assisting gunner, who drops the live round on command. Teams practice every day for months to develop a flawless rhythm.

The 60 mm mortar can be fired on the ground or in a handheld configuration.


A lot of different considerations go into firing this weapon.

Ryan Pickrell/Business InsiderThe assisting gunner loads the the round.

There is the gun. “You can breathe on it the wrong way, and it will be completely off,” Rodriguez told Insider.

There is the round. Mortar crews can set it to burst in the air, explode on impact, or detonate a few seconds after impact, giving it the ability to penetrate a bunker.

Then there is figuring out exactly how to get the round to the target, and that involves different range calculations, as well as considerations like temperature, wind speed, and drift, among other things.

Weather is also an important factor. Rain, even light rain, for example, can result in wet charges, making a misfire or the firing of a short round more likely and risking a friendly-fire situation. There are covers to help protect the weapon and the rounds from the elements.


There are two different methods Marine mortar teams use to effectively target an enemy.

Ryan Pickrell/Business InsiderThe assisting gunner prepares to drop the round.

Range calculations are estimations at best. An experienced mortarman can eyeball the distance to his target, but it tends to take a few shots to get rounds falling in the right spot.

The quickest and most effective targeting approach is called bracketing. Mortar crews fire behind or in front of a target and then split the distance in half until rounds are coming down on the target.

Or, as Insider watched a crew do at Camp Pendleton, Marine mortar crews can use creeping fire to target an enemy, inching closer to the target with each round. This is not as fast as bracketing and requires more rounds, about five or six.

But creeping fire can be a pretty good option when you’re dealing with a lot of dead space, terrain features that make range estimates harder.


A mortar section usually has three guns delivering damage to a large area.

US Marine Corps/Lance Cpl. Robert KuehnA close-up shot of the three main crew members as the round exists the tube.

Mortars set the conditions for other units by keeping bigger threats at bay.

The mortar crews are tasked with “taking out the bigger targets, or at least keeping their heads down long enough for the machine guns to start suppressing enemies,” Rodriguez said. “The [other infantry units] are more the cleanup. They can move from one place to another.”

During the training at Camp Pendleton, the mortars practiced pinning down light armour while crews with M240 machine guns put fire on targets from a nearby ridge.

The mortars and the machine guns cleared the way for several infantry squads to manoeuvre into position. Each mortar round has a casualty radius of about 25 meters.

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