One of the first polymer case ammunition rounds for wide production in the Marine Corps will be for its heavy duty machine gun, the venerable M2 .50 caliber Browning Machine Gun.

The Marine Corps recently announced its intent to sole source a company to build polymer casings for .50 caliber ammunition, the largest direct fire, bullet projectile in the ground combat arsenal and a mainstay of machine gunning for nearly a century.

MAC LLC, a company out of Bay Saint Louis, Mississippi, is the company that will likely receive the sole source contract unless another company can show they meet the requirements and can do a better job before the federal deadline in a couple of weeks to deliver an estimated quantity of 2.4 million cartridges for the Corps over three years.

It will be producing both ball and armor-piercing rounds.

The weight savings sought by the Corps aims to cut 20 pounds off of the current weight of a can of .50 caliber ammunition, or a cut of up to one-third of the existing load.

Marine Corps Systems Command posted the request in April 2018 and awarded this contract this April 1, according to a posting on fbo.gov, a federal government business website.

A belt of 100 lightweight .50-caliber cartridges with 101 links will have to see a 15 to 30 percent weight reduction under the Corps’ requirements listing.

Marines with Regimental Surveillance and Target Acquisition Company use .50 caliber ammunition to fire the .50 caliber sniper rifle during RSTAC live fire training at Fort Irwin, California. (Lance Cpl. Alexa M. Hernandez/Marine Corps)
Marines with Regimental Surveillance and Target Acquisition Company use .50 caliber ammunition to fire the .50 caliber sniper rifle during RSTAC live fire training at Fort Irwin, California. (Lance Cpl. Alexa M. Hernandez/Marine Corps)

And no performance can be sacrificed — the new cartridge must meet the same ballistics requirements and lethality of the M33 projectile in service now.

Polymer is the new steel in many of weapons accessories and ammo casings.

The Corps authorized the use of polymer magazines for the M27 Infantry Automatic Rifle in recent years.

An ongoing Army program to build the Next Generation Squad Automatic Rifle, a parallel project to replace both the M4/M16 carbine/rifle and the Squad Automatic Weapon, is taking on submissions with polymer cased-telescoped ammunition.

One such version is the Textron Systems offering. Textron has spent years building a polymer-cased ammunition and essentially redesigned a weapon system around the new round.

All of these are part of larger efforts across the services to lighten the load with new materials, designs and configuration of everything from body armor to weapons systems and ammunition.