M712 Copperhead

The projectile has a minimum range of 3 km (1.9 mi) and a maximum range of 16 km (9.9 mi).

The concept for Copperhead was originally made in 1970 by engineers at the US Army's Rodman Laboratories, with feasibility studies conducted in 1971. In 1972 development contracts were awarded to Martin Marietta and Texas Instruments. After testing Martin Marietta was chosen for continued development through the 1970s.

Copperhead has two modes of operation: ballistic mode and glide mode. Ballistic mode is used where the cloud ceiling is high and visibility is good. When the projectile is 3,000 m (9,800 ft) from the target, the guidance vanes extend, the target is acquired, and then the on-board guidance system adjusts the guidance vanes to maneuver onto the target. Glide mode is used when the cloud ceiling and/or the visibility is too low to permit the use of the ballistic mode. A glide mode trajectory consists of two phases: a ballistic phase and a glide phase. At a predetermined point along the trajectory, the guidance vanes extend and there is a transition from ballistic phase to glide phase. Glide phase targeting logic is designed to ensure the largest possible angle of fall permitted by the cloud cover and the visibility. The target is acquired when the projectile is close enough to detect the laser illumination or when the projectile emerges from the cloud cover, whichever event occurs later in the trajectory. When a trajectory solution has been obtained, time-to-target and terminal velocity are checked to ensure that there will be enough time to maneuver and that the projectile is aerodynamically stable—that it will not stall while maneuvering. Initially the laser designation was intended to be performed by the MQM-105 Aquila pilotless drone.

Copperhead was used in Operation Desert Storm, with 90 rounds fired against hardened Iraqi fortifications and radar stations. One of these strikes caused an Iraqi unit to surrender. Lebanese Armed Forces fired several hundred Copperhead shells at ISIL targets in east Lebanon during the Qalamoun offensive (July–August 2017). At least five technicals, five occupied buildings, and several troop formations were struck with precision. In 2018 the US delivered 827 Copperhead shells to the Lebanese Armed Forces in an aid package alongside Bradley fighting vehicles and MK19 40mm grenade launchers. Ukraine's military confirmed employing Copperhead shells to strike a Russian communications tower in Kursk in November 2024, and a command bunker in Kherson 2025.

United States Egypt Jordan Lebanon Taiwan Ukraine

Australia – now replaced by SMArt 155.