The U.S. Army's chief of staff revealed Thursday the M4 Carbine's 5.56mm round can't penetrate modern enemy body armor plates and plans to arm infantry units with rifles chambered for a more potent 7.62mm cartridge.
Responding to questions from Senate Armed Services Committee members, Gen. Mark Milley conceded that the service's current M855A1 Enhanced Performance Round will not defeat enemy body armor plates similar to the U.S. military-issue rifle plates such as the Enhanced Small Arms Protective Insert, or ESAPI.
"The 5.56mm round, we recognize that there is a type of body armor out there, that it doesn't penetrate. We also have that body armor ourselves," he testified.
"We have developed a pretty effective round down at Fort Benning," he said. "We know we have a bullet that can penetrate these new plates."
Sen. Angus King, I-Maine, asked if the new bullet will require a new rifle.
Milley said, "It might but probably not," adding that weapons can be chambered for various calibers.
However, the M4 would require a new barrel, bolt carrier group, buffer system in addition to a new lower receiver to shoot 7.62mm ammo, experts maintain.
He later told Sen. Joni Ernst, R-Iowa, there are systems on the shelf today that, with some very minor modifications, could be adapted to meet the Army's needs.
"I think there are weapons out there that we can get in the right caliber that can enhance the capability of the infantry soldier," Milley said.
He also told lawmakers that not every soldier will need a 7.62mm rifle.
"This idea that the entire Army needs the same thing all the time, it's not necessarily true," Milley said. "There are some infantry units that are much more highly likely to rapidly deploy than others and conduct close-quarters combat that we would probably want to field them with a better-grade weapon that can penetrate this body armor that we are talking about."
The subject of the 5.56mm round being underpowered came up at a May 17 hearing before the Senate Armed Services Committee's Airland Subcommittee. Retired Lt. Gen. John Bednarek and retired Maj. Gen. Robert Scales Jr. testified at the hearing about the U.S. military's future small-arms requirements.
Ernst said that Scales testified about "a weapon that could fill the role of the light machine gun and the rifle."
"Is the need for a machine gun a higher priority than just a basic rifle?" she asked.
Milley said that infantry units need both to be effective. "I think what [Scales] is talking about is the Marines are adopting ... the M27" infantry automatic rifle, a version of the 416 made by Heckler & Koch.
"We are taking a hard look at that and are probably going to go in that direction as well, but we haven't made a final decision on it," Milley said. "The infantry squads and infantry platoons -- they've got to have an automatic weapon for suppression; they've got to have the individual weapon as well, so you need both ... to be effective in ground combat."
Sen. Jack Reed, D-Rhode Island, asked if the new 7.62mm round would still be considered a standardized NATO round that could be used by allied countries.
"It's a 7.62mm round, so I think the answer is yes," Milley said, promising to get a more detailed answer.
This is not the Army's first effort this year to equip infantry squads with 7.62mm rifles.
A recent directed requirement from Vice Chief of Staff Gen. Daniel Allyn prompted Army weapons officials to write a new requirement, and most likely they will conduct a competition that will result in the service equipping each combat arms squad with a new 7.62mm squad designated marksman rifle, said Matt Walker, deputy for the Lethality Branch at the Maneuver Center for Excellence at Fort Benning, Georgia.
-- Matthew Cox can be reached at firstname.lastname@example.org.