Laying out muzzles

As the morning begins, instructors at the Infantry Immersion Trainer lay out the gear that Marines will use as they train. The troops will be firing live but will use special bullets topped with soap that are essentially like paintballs. Here, one of the instructors lays out the muzzles that are used to shoot the special bullets.

Magazines and masks

Members of the Marines' 6th Engineer Support Battalion -- a reserve unit -- have come to Camp Pendleton from their bases in Tucson, Ariz., and Bakersfield, Calif., to take part in the Infantry Immersion Trainer.

Although they will be firing special, non-lethal ammunition, they must still wear protective gear, such as the masks on the left. On the right are magazines full of the special ammunition.

Gear line

Marines line up to get their gear for their day at the Infantry Immersion Trainer. They are carrying M-16s without muzzles and will be given a muzzle that has been configured for shooting the special, non-lethal ammunition.

Milling about

A Marine inspects his M-16 as he and his fellow troops mill about prior to beginning their day at the Infantry Immersion Trainer.

Briefing from the major

Major Lucas Castanos of the U.S. Marines 6th Engineer Support Battalion briefs his troops on what they'll be going through in the Infantry Immersion Trainer.

Masking up

A squad of Marines puts on their protective masks as they prepare to enter the Infantry Immersion Trainer.

Going over plan

An instructor named Darren briefs a group of squad leaders on the layout of an indoor "town" they'll be leading their troops into. Each squad would enter the town on "presence patrol" and would have to suppress an insurgent that fires at them.

Patrolling the alley

Several Marines point their weapons down an alley as they patrol the "village" that is meant to resemble an Afghan town.

Kicking door

A Marine kicks open a door during his squad's patrol.

Running and shooting

The sniper has opened fire on the Marines as they've entered a public marketplace. Here, a Marine runs across the square firing at the sniper's position as several of his squad cover him.

Villagers

Before the Marines arrive, several "villagers," civilians hired by the Marines to help make the IIT more realistic, mill around the marketplace.

Coming out shooting

A Marine runs out from behind a wall shooting.

Darren observing

Darren, the IIT instructor, kneels as he looks on at the Marines going through the scenario inside the Infantry Immersion Trainer.

The bullet

This is one of the non-lethal bullets used in the IIT training. It is topped with a material made from soap that leaves marks, but won't injure or kill those it hits.

Against the fence

A squad of Marines prepares their weapons for the trainer. They are facing the fence because it guarantees they won't accidentally fire their weapons at anyone.

Discussing the plan in the dirt

Marine Sgt. Gerry Apple goes over the plan for his squad as they ready to enter an outdoor "town" that is part of the Infantry Immersion Trainer. Marine Capt. Jeremy Masten (foreground) looks on and offers feedback.

Entering the town

A squad of Marines enters the outdoor area of the IIT, which is meant to resemble an Afghan town.

Greeting a local

A Marine shakes hands with a "villager." The Marines are trained to try to maintain cordial relationships with the locals.

Peeking around a corner

Two Marines peek around a narrow corner as they patrol the outdoor area of the trainer, trying to find a shooter who has opened fire on their squad.

Instructor watching at bottleneck

An instructor watches several Marines as they are about to make their way through a bottleneck. The instructor is shouting various commands and feedback at them as they work.

Translator firing

The squads are accompanied by a "translator" who helps them converse with the locals. Here, the translator fires at an attacker as the squad has gotten caught in a surprise attack.

IED goes off

The Infantry Immersion Trainer is designed to prepare the Marines not just for dealing with with attackers firing at them with guns. In addition, it features other surprise dangers, including improvised explosive devices.

Running to man down

Instructors also serve as referees, calling out when someone is shot or "killed" by something like an IED. Here, several Marines run over to help a comrade who has been "hit" by an exploding IED.

Covering

Three Marines cover another who is carrying a "wounded" comrade over his shoulder.

On the move

A Marine runs in the middle of a scenario in the Infantry Immersion Trainer.

Dragging off injured

A Marine drags off a wounded comrade in the middle of a training scenario.