It's the job of Marine infantry to close with the enemy and overwhelm them with firepower.

But in most cases, doing that doesn't require fully automatic weapons — in fact, they can have drawbacks.

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The primary mission of a US Marine infantry rifle squad is to locate, close with, and destroy the enemy by fire and maneuver or to repel the enemy's assault by fire and close combat. This mission statement is branded into each infantryman's brain and consistently put to practical use when the grunts are deployed to the front lines.

In the event a Marine infantry squad takes enemy contact, the squad leader will order the machine-gunners to relocate themselves to an area to return fire and win the battle for weapon superiority. The squad leader will also inform his fire team leaders of the situation and they'll deploy their two riflemen and SAW (Squad Automatic Weapon) gunner to a strategic area — getting them into the fight.

Once they have a fix on the enemies' position, they'll call the mortar platoon to "bring the rain."

At literally the flip of a switch, troops go from having a cold weapon system to knocking a fully automatic weapon, bringing death to the bad guys at the pull of a trigger.

This sounds super cool, right? Well, it kind of is when you've experienced the situation first hand. We understand that having a fully automatic machine gun gives troops a commanding advantage, but when you look at how ground pounders are trained to fire the weapon system, the rate of fire nearly mirrors that of an M4's after a few bursts.