On June 23, 2010, U.S. Army representatives announced that they had started shipping that service’s new 5.56mm cartridge, designated the M855A1 Enhanced Performance Round, to support warfighters in Afghanistan.

The new M855A1 round, which will replace the current M855 5.56mm cartridge that has been used by U.S. troops since the early 1980s, is sometimes referred to as “green ammo” since it contains an environmentally friendly projectile that reportedly eliminates up to 2,000 tons of lead from the manufacturing process each year.

The Army launched the M855A1 program in September 2005 as a Congressionally mandated initiative to replace the lead core M855 cartridge. In addition, the program focused efforts on developing a new round that would address what service planners dubbed “perceived shortcomings” with the current M855 used in short barreled weapons like the M4.

According to program participants, the program team, comprised of Project Manager, Maneuver Ammunition Systems (PM-MAS), Army Research Laboratory (ARL), U.S. Army Armaments Research Development and Engineering Center (ARDEC), and ATK team members, evaluated more than 20 potential projectile designs before moving forward with a three-piece, reverse-jacket bullet design incorporating a hardened steel penetrator and lead-free slug.

While Army representatives highlight ballistic test results for the new M855A1 cartridge that showed “improved performance over M855 at both long and short ranges, and across an array of target sets,” the round raised eyebrows following recent reports that the Marine Corps dropped plans to field the M855A1 in favor of fielding the special operations’ MK 318 Mod 0 for Marines in Afghanistan.

In announcing the late June 2010 shipment of the M855A1 round to Army warfighters, service representatives highlighted “a number of significant enhancements not found in the current round. These include improved hard target capability, more dependable, consistent performance at all distances, improved accuracy, reduced muzzle flash and a higher velocity.”

“During testing the M855A1 performed better than current 7.62mm ball ammunition against certain types of targets, blurring the performance differences that previously separated the two rounds,” the announcement read, and continued, “The projectile incorporates these improvements without adding weight or requiring additional training.”

Describing the projectile as “the best general purpose 5.56mm round ever produced,” Lt. Col. Jeffrey K. Woods, M855A1 product manager, characterized the fielding as ”the most significant advancement in general purpose small caliber ammunition in decades.”

U.S. Army Project Manager, Maneuver Ammunition Systems Chris Grassano called the fielding “the culmination of an Army enterprise effort by a number of organizations, particularly the Army Research Laboratory, Armament Research Development and Engineering Center, Program Executive Office for Ammunition and the Joint Munitions Command.

“The Army utilized advanced science, modeling and analysis to produce the best 5.56mm round possible for the warfighter,” he said.

The M855A1 is tailored for use in the M4 weapon system, but is also credited with “vastly” improving the performance of the M16 and M249 families of weapons.

Pointing to “more than one million” M855A1 rounds fired during testing to date, program representatives noted that the new cartridge recently completed the limited rate initial production (LRIP) phase and is beginning the follow-on full rate production phase where they plan to procure more than 200 million rounds over the next 12-15 months.

Soldiers in Afghanistan will begin using the M855A1 in the summer of 2010.