Ordnance Notes -- by Bob Stoner GMCM(SW) Ret

Ordnance Notes -- by Bob Stoner GMCM (SW) (Ret.)

M72 Series Light Anti-Tank Weapon (LAW)

The M72 Series LAW was the successor to the M20 Series 3.5-inch rocket launcher. The M20 was a Korean War developed weapon that replaced the M1, M9, and M18 2.36-inch rocket launchers of World War 2. Users felt the M20 was too big and bulky.

A Korean War M20 3.5-inch rocket launcher with its integral bipod extended. This was an improved, larger caliber version of the M1, M9-series, and M18 2.36-inch rocket launchers of World War 2. The M20 weighed approximately 15 pounds and was over 5 feet long. (Photo: US Army)

The solution to the heavy and awkward M20 rocket launcher was the 66mm M72 Light Anti-Tank Weapon (LAW). The LAW design was a one-shot, disposable, anti-tank rocket launcher. First M72 LAWs were fielded by the Army in the early 1960s. The M72 was totally man-portable and was issued as a pre-packaged round of ammunition. The M72 could penetrate 12 inches of armor and had a range of 170 to 220 meters. It became a NATO standard weapon and was copied and produced by Czechoslovakia and Russia as the RPG-18 and RPG-26.

“Fire in the hole!” A photo by SEAL Steve Ellison shows an M72 LAW being fired from the helo deck of the HSSC. The M40A1 106mm recoilless rifle is directly behind the shooter. Note that everyone except one guy has covered his ears to protect them from the noise of the rocket blast. It would appear that some folks need to learn the hard way. He would certainly want to cover them when the 106mm was fired; its blast was much, much louder. (Photo: Steve Ellison).

The M72 required little from the user -- only a visual inspection and some operator maintenance. The launcher consisted of two tubes that telescoped inside each other and formed a watertight packing container for the rocket. A percussion-type firing mechanism was used to fire the rocket. The M72 had three basic parts: (1) outer tube, (2) inner tube, and (3) rocket.

OUTER TUBE. The outer tube contained the trigger housing (which housed the trigger), the trigger arming handle, front and rear sight assemblies, and tube covers.

INNER TUBE. The inner tube telescoped from the outer tube to the rear, guided by a channel assembly and alignment slot. The channel assembly also contained the firing pin rod which included a detent assembly. The detent lever assembly moved under the trigger, and was cocked when the tubes locked into firing position.

ROCKET. The rocket was percussion-ignited, fin-stabilized, fixed ammunition. It was attached by the igniter to the inside of the launcher. The rocket was a 66mm HEAT round with a piezo-electric point-initiated, base-detonating fuze and a rocket motor. Six spring-loaded fins popped out when the rocket left its launch tube. When ignited, the propellant in the rocket motor burned completely before the rocket left the tube. The gas pressure pushed the rocket toward the target and exited to the rear of the launcher as back blast.

The components of the M72 Light Anti-tank Weapon (LAW): the 66mm fin-stabilized HEAT rocket; the launcher tubes extended and sights erected; and the end caps with the carrying sling.
(Photo: US Army)

M72 LAW TECHNICAL DATA.

Launcher extended -- 34.7 inches.
Launcher closed -- 24.8 inches.
Weight (M72A2) -- 5.1 pounds; (M72A3) -- 5.5 pounds.
Firing mechanism -- percussion.
Rocket -- 66mm HEAT.
Rocket Length -- 20 inches.
Rocket Weight -- 2.2 pounds.
Rocket Muzzle velocity -- 475 feet per second.
Rocket minimum combat or arming range -- 33 feet.
Rocket maximum effective range (stationary) -- 660 feet; (moving) -- 541 feet. Rocket maximum range -- 3300 feet.

Close-up of a soldier firing the M72 from the prone position. (Photo: US Army)