Skip to main content

Video Above: Army AI Task Force Speeds Attacks - Soldier Decisions

byDavid AxeFollow @daxe on TwitterL

The U.S. Army is making progress in developing a new bullet that can penetrate body armor. The 6.8-millimeter-diameter projectile could help the ground-combat branch to defeat sophisticated enemy forces whose troops wear the same kind of armor that American troops do.

The development of the new round dovetails with Army’s Next Generation Squad Weapon program, which aims to field a new rifle and squad machine gun that can fire the larger, more powerful bullet.

Sources told that the new round includes an exposed steel penetrator that sits on top of a copper slug and is partially encased in a copper jacket. The higher-performing ammo could extend the effective range of an Army rifleman from around 300 yards to around 600 yards.

A 2017 research initiative prompted the Army to go with the 6.8-millimeter round. Current squad weapons fire 5.6-millimeter-diameter rounds such as the M855A1. “That report convinced Army leaders that infantrymen need a round that would penetrate enemy body armor much more effectively than the current M855A1,” noted.

The 5.56-millimeter round long has been an object of scorn in the U.S. military. “A push in the late 1950s toward a lightweight rifle with lightweight ammunition led to the adoption of the 5.56-millimeter [round], based on the .223 Remington round, typically used for small game or varmint hunting in the United States,” Military Timesexplained.

At the time, the lightweight, high-velocity rounds were considered more accurate, causing more devastating wounds from the tumbling of the round and fragments, and an effect known as “hydrostatic shock” — though a number of critics have since disputed both assumptions.
By 2002, Army small arms and ballistics researchers were looking at intermediate caliber options after military arms officials began receiving “numerous complaints about the terminal performance” of the standard 5.56-millimeter ammunition used in combat at the time.

Scroll to Continue

Recommended for You

It took a decade for that research to produce a program of record for new ammo, which in turn propelled the squad-weapons program.

"If you want to build a new innovative weapon, you start with the ammunition; you don't start with the weapon and try to back into the ammunition -- that is not the most effective means to do it," said Brig. Gen. Anthony Potts, the head of the Army’s Program Executive Office Soldier.

"In the end ... there is no secret, it's all about energy on target,” Potts continued. “So, we have to understand the targets that we are going after, we have to understand how much energy it takes to defeat that target at that distance, and we have to build a system that delivers that."

The Army briefly considered adapting current weapons such as the M4 rifle and Squad Automatic Weapon machine gun to fire the larger round. It’s not clear that such adaptation even would be possible.

“From the start, this ambitious performance goal created concerns in the firearms community — particularly penetrating body armor would require much higher velocities than the M855A1’s … 2,970 feet per second,” explained. “Higher velocities often come with higher chamber pressures, which can cause premature parts wear and reliability problems over time.”

"Higher pressures in the weapon drive all sorts of unsavory things -- barrel wear … the stresses that go back on the bolt face, extraction [problems], premature part wear -- there's all sorts of unfavorable things higher pressure drives," Dave Stouffer, director of business development for a General Dynamics-led team that is one of three bids on the NGSW program, told

The Army plans to produce the new 6.8-millimeter ammo at a factory in Lake City, Missouri. Ammunition-maker Winchester won the contract to run the Lake City plant starting in 2020. The Army plans to select a winning design for the NGSW rifle and machine-gun some time in 2022.

The Marine Corps and U.S. Special Operations Command also could adopt the new guns and ammo.

David Axe serves as Defense Editor of the National Interest. He is the author of the graphic novels  War Fix,War Is Boring and Machete Squad.