The Army has quintupled its order for an interim service rifle in 7.62 mm, which it needs to pierce enemy body armor and the current 5.56 mm round just won’t do.

The Interim Combat Service Rifle, first referred to in a May 31 request for information that sought 10,000 rifles from commercial, off-the-shelf sources, has now shifted to a Commercial Opportunity Notice asking for industry to be able to produce 50,000 of the rifles in 7.62 mm.

The actual order requirement of 10,000 rifles remains the same. The Marines recently made the same adjustment with the M27, a 5.56 mm Heckler & Koch-made rifle they are replacing the M4 with over the next three years in every infantry squad.

A Marine official said their increase in production requirements would allow the Marines to procure more rifles should funding and operational requirements change.

The request is specifically to meet a “potential gap in the capability of ground forces and infantry to penetrate body armor using existing ammunition.”

The new post went online Aug. 4 and is giving industry until Sept. 6 to submit proposals and sample rifles for testing.

The rifle must pass tests using the M80A1 Enhanced Performance Round, which industry insider website The Firearm Blog has tracked, tested and reviewed ballistic performance on for years. The site gave the round substantially high marks for penetration and accuracy.

The weapon must include enough magazines to support the 210-round requirement, be suppressor ready and have both semi- and full-automatic firing capabilities.

What remains to be seen is how a rifle in the larger 7.62 mm caliber could change the way ground combat troops fight.

In congressional testimony this spring, retired Maj. Gen. Robert Scales and Lt. Gen. John Bednarek advocated for a new intermediate caliber round that falls between 5.56 mm and 7.62 mm in the 6.5 mm range to meet lethality, range and penetration needs.

Weapons experts at the Army’s Maneuver Center of Excellence are working on multiple variants of a rifle in that intermediate caliber, which is likely to fully replace the current M4/M16 rifle being carried by most soldiers.

Officials at the Maneuver Center did not provide comment on changes to the Interim Combat Service Rifle request as of press time.

In May, Army Chief of Staff Gen. Mark Milley told Congress that the Army had developed a bullet that would penetrate 5.56 mm-resistant body armor. The four-star was quizzed by Sen. Angus King, I-Maine, as to whether the Army was looking at a new rifle to replace the M4 and if the new bullet would need a new rifle.

Milley said at the time that it might require a new rifle.

Marines have purchased and continue to procure the Heckler and Koch 417, dubbed the M27, in 5.56 mm. Army officials have purchased the same rifle recently in 7.62 mm for their squad designated marksmen.