In a recent USMC Iraq incident after action report, there was a table listing all of the Class V (ordnance) items carried on the Cougar vehicle used during the incident. The one unfamiliar item was a listing for an M72A5.

First fired in October 1959, the Lightweight Anti-Tank Weapon (LAW) was a U.S. Army project based on a design by the Hesse-Eastern Division of Flightex Fabrics, Inc. Type classified in March 1961 as the M72 High-Explosive Anti-Tank (HEAT) rocket, the original LAW had a 2.6 inch (66 mm) diameter shaped charge warhead that was designed to penetrate 11.8 inches (300 mm) of mild steel and light field fortifications at ranges from 11-219 yards (10-200 meters). Propelled by a solid fuel propellant, the rocket utilized six folding fins for stabilization and reached a velocity of 500 feet (152 meters) per second. The disposable launcher was comprised of two interconnected tubes, with the forward (outer) tube being constructed of a fiber glass composite and the rear (inner) tube being constructed of aluminum. Immediately prior to firing, the operator was required to remove the covers from the forward end of the front (outer) tube and the rear of the rear (inner) tube and pull the rear (inner) tube to the rear, fully extending the launcher to approximately 35 inches (900 mm). Extending the rear (inner) tube simultaneously cocked the launcher’s firing pin, released the safety interlocks, and caused the integral sights to move via springs into firing position. Due to the open tube design, recoil was minimal to non-existent; however, back blast from the rocket firing could damage equipment or personnel up to 39 yards (36 meters) away from the launcher’s rear tube. Weight of the launcher with the rocket was 5.1 pounds (2.3 kg).

The M72A1 and M72A2 LAWs offered improved sights and a more powerful rocket motor over the M72, while the M72A3 provided safety upgrades to the rocket’s fuzing system. The more powerful rocket motor increased the effective and operational ranges to approximately 186 yards (170 meters) and 273 yards (250 meters), respectively, and increased the back blast danger area to 43.7 yards (40 meters). Weight of the system (rocket and launcher) increased to 5.5 pounds (2.5 kg).

In the mid 1980s, Talley Defense Systems began work on the improved LAW system, specifically the M72A4, M72A5, and M72A6 models. All share an improved rocket motor that increases rocket velocity to 650 feet (198 meters) per second and increases the effective and operational ranges to 241 yards (220 meters) and 383 yards (350 meters), respectively. However, back blast danger area increased to 76.5 yards (70 meters). Weight of the new systems is 7.9 pounds (3.6 kg), and the extended launcher length is 38.6 inches (980 mm). The primary difference in the newer models is the type of warhead utilized.

The M72A4 incorporates an improved shaped charge warhead explosively-filled with Octol that when coupled with the improved rocket motor, increases penetration capability against rolled homogeneous armor (RHA) to 14 inches (355 mm).

The M72A5 is the same shaped charge warhead utilized in the M72A3 model (differing only by utilizing Octol as the explosive fill) coupled to the new rocket motor. While the RHA penetration is the same as that achieved with the M72A3, the newer rocket motor increases the effective and operational range of the weapon.

A copper shaped charge warhead works well against solid steel targets. Against layered steel targets with air gaps or against masonry, it is far less efficient. For these types of targets, the M72A6 was developed. Utilizing an explosively formed penetrator (EFP) warhead that is explosively-filled with Octol, the M72A6 can penetrate 5.9 inches (150 mm) of RHA or can blast a man-sized hole in bricks, concrete, and masonry in urban environments when expedient breeching is required. The M72A7 contains the same EFP warhead, only the insensitive high explosive PBXN-9 is utilized as the explosive filler.

Models currently under development include a model that will allow firing from an enclosure (no damage to operator from back blast), an increased (to 17.7 inches or 450 mm) RHA penetration capability, and an anti-personnel model.

The primary components of the weapon are the barrel, muzzle cover, firing mechanism, the sights and the projectile. The barrel is a composite glassfibre reinforced plastic that has an aluminum venturi at the exhaust end. The muzzle cover is rubber and acts as a shock absorber. The firing mechanism is a simple spring-loaded bolt-like device that is pushed forward until it locks in place, readying it for firing. The adjustable sights are simple and rugged, utilizing spring loaded polymer panels factory preset to 200 meters, that are stored beneath sliding polymer covers that are meant to protect the sights during transport and storage. The projectile is what is referred to as an 84mm HEAT (High Explosive Anti-Tank) round.

The 84mm HEAT round is composed of a cartridge case and the HEAT shell. The HEAT shell has four primary components, these being the fin assembly, base fuse, stand-off cap and HMX/TNT hollow charge. Upon discharging the HEAT round, the fins open to stabilize the rocket in flight. The fuse is constructed with an out-of-line detonator safety device that prevents accidental initiation. When the stand-off cap portion has traveled a minimum of ten meters (thirty-three feet) and it impacts the target, an impact sensor activates the fuse which in turn detonates the HMX/TNT hollow charge. The result is tremendous behind armor damage that is a combination of overpressure, intense incendiary effects and spalling.

The round is quite effective as evidenced by a better than 97 percent close-in armor defeat ratio and in excess of 500,000 units have been produced. This weapon system is in service not only in the United States, but also in the Swedish Army, the Brazilian Army and Navy, Danish Army and the Netherlands.

There are special variations of this weapon produced for training purposes and all weapons are color coded to signify which system you have. A plain black band or a black with yellow band indicates a HEAT round. A gold or yellow band indicates a field handling trainer and no band is indicative of the M287. The M287 is a 9mm sub-caliber trainer that utilizes a reduced powder loaded 9mm NATO (9x19mm, 9mm Parabellum) caliber tracer cartridge (designated M939) that simulates the ballistics of the 84mm HEAT round for training target practice purposes.