Army Chief of Staff Gen. Mark Milley told senators Thursday that the Army has developed a round that can penetrate 5.56 mm-resistant body armor.
During a Senate Armed Services Committee hearing on the Army's budget request, Sen. Angus King, I-Maine, asked Milley how the Army was doing in developing a new rifle to replace the M4 and a more powerful round to replace the 5.56 mm bullet it fires.
"We think we have a solution," Milley said. "We know we have developed a bullet that can penetrate these new plates."
Milley said that rifles and body armor for U.S. troops are "critically important," noting that 70 percent of U.S. casualties are borne by ground troops, mostly infantry and special operators conducting infantry-type missions.
"The 5.56 round, we recognize there is a type of body armor it does not penetrate, and adversarial states are selling that stuff on the Internet for about 250 bucks," Milley said.
Army Times reported earlier this month that experts at the Army's Maneuver Center of Excellence at Fort Benning, Georgia, were testing half a dozen variants of "intermediate caliber" bullets that fall between the 5.56 mm and 7.62 mm rounds now used by nearly all U.S. troops.
Milley emphasized that the focus for lethality is on the bullet, not the rifle.
King asked if the new bullet would require a new rifle.
"It might, but probably not," Milley replied.
The senator then asked if there were existing, off-the-shelf rifle options.
"Yes, there are several options out there," Milley said.
King was among a handful of senators at a subcommittee hearing last week who heard from retired Army generals long advocating for a new round and rifle to replace both the M4 and the 5.56 mm round.
The Marines are purchasing the Heckler and Koch 417, dubbed the M27, in 5.56 mm, while the Army is purchasing the same rifle in 7.62 mm for squad designated marksmen.