The XM1113 Insensitive Munition High Explosive Rocket Assisted Projectile, or XM1113 RAP, will replace the aging M549A1 rounds produced in the 1970s and 1980s. Pictured, 155mm artillery rounds are prepared to to load and fire the Paladin M109A6 self-propelled howitzer. U.S. Army photo by Sgt. Ashley Marble

PICATINNY ARSENAL, N.J., Aug. 26 (UPI) -- A new 155mm artillery round with extended range is being developed by the U.S. Army.

The XM1113 Insensitive Munition High Explosive Rocket Assisted Projectile, or XM1113 RAP, will replace the aging M549A1 rounds produced in the 1970s and 1980s.


"The XM1113 provides the user with cannon-launched munitions to engage targets out beyond the current 30-kilometer (about 18.6 mile) capability," said Ductri Nguyen, XM1113 Integrated Product Team Lead. "The new projectile is currently designed to reach 40-plus kilometers (about 24.8 miles) and will be compatible with the existing M1156 Precision Guidance Kit (PGK) that provides near precision strike capability."

The U.S. Army's Picatinny Arsenal said soldiers can screw the PGK fuze into the fuze well of conventional 155mm high-explosive cannon artillery projectiles, replacing the standard fuze. This allows troops to turn their conventional artillery rounds into "smart" munitions with near precision accuracy.

The new artillery round will achieve extended range through increased thrust and a re-engineered artillery shell shape.

"The XM1113 uses a large high-performance rocket motor that delivers nearly three times the amount of thrust when compared to the legacy M549A1 RAP," said Nguyen. "Its exterior profile shape has also been streamlined for lower drag to achieve the 40-plus kilometers when fired from the existing fielded 39-caliber 155mm weapon systems."

The rocket-assisted projectile can be fired from the currently fielded M777A2, Nguyen added.

The new round also features the use of insensitive munition explosive instead of traditional high explosive. The insensitive munition explosive is less volatile and reactive to outside stimuli, such as rocket-propelled grenades, improvised explosive devices and extreme high temperatures.

The XM113 program is a joint development between the Armament Research, Development and Engineering Center and the Program Executive Office Ammunition, both located at Picatinny Arsenal.

The XM1113 is planned for limited rate initial production in fiscal year 2022.