Design
On impact, the nose cover collapses, crushing a crystal-like material, which sends an electric current through a separate wire to the warhead's detonator, located in the base of the warhead. A mechanical safety, comprising a set back system located in the warhead's base, grounds the firing circuit and prevents the accidental explosion of the warhead. On firing, the sudden launch acceleration causes the set-back's three disks to rotate 90 degrees, each in succession to the other, with the rotation of the third disk removing the grounding after approximately 10 meters of flight and completing a firing circuit for the current to flow from the nose to the detonator in the base. Compared to the ENERGA, the M31 is slightly lighter in weight and has a smaller-diameter warhead—i.e. 75 mm (3.0 in) vs 66 mm (2.6 in). Penetration for the M31 is estimated to be 200 mm / 8 inches for steel armor plating [4] [5] and twice that estimate for concrete. The warhead technology developed for the M31 was used for the future M72 LAW antitank rocket.
Status
Various US military manuals issued in 1972 still had sections on the M31, but by the end of the Vietnam War, both the US Army and US Marines had essentially phased out muzzle-launched rifle grenades, in favor of the M72 LAW disposable rocket in the anti-armor role and the M203 under-barrel grenade launcher in the squad fire-support role.
In the 1977 revision of US military anti-armor warfare manuals, the M31 HEAT was no longer listed. [6]
The 2001 U.S. Army TM 43-0001-29 C2, "Data Sheets for Grenades" details the Grenade, Rifle, HEAT M31 on pages 3-3 and 3-4 with DODIC ordering codes.
A rocket-propelled grenade (RPG) is a shoulder-fired missile weapon that launches rockets equipped with an explosive warhead. Most RPGs can be carried by an individual soldier, and are frequently used as anti-tank weapons. These warheads are affixed to a rocket motor which propels the RPG towards the target and they are stabilized in flight with fins. Some types of RPG are reloadable with new rocket-propelled grenades, while others are single-use. RPGs are generally loaded from the front.
A bazooka is a man-portable recoilless anti-tank rocket launcher weapon, widely deployed by the United States Army, especially during World War II. Also referred to as the "stovepipe", the innovative bazooka was among the first generation of rocket-propelled anti-tank weapons used in infantry combat. Featuring a solid-propellant rocket for propulsion, it allowed for high-explosive anti-tank (HEAT) shaped charge warheads to be delivered against armored vehicles, machine gun nests, and fortified bunkers at ranges beyond that of a standard thrown grenade or mine. The universally applied nickname arose from the M1 variant's vague resemblance to the musical instrument called a bazooka invented and popularized by 1930s American comedian Bob Burns.
High-explosive anti-tank (HEAT) is the effect of a shaped charge explosive that uses the Munroe effect to penetrate heavy armor. The warhead functions by having an explosive charge collapse a metal liner inside the warhead into a high-velocity shaped charge jet; this is capable of penetrating armor steel to a depth of seven or more times the diameter of the charge. The shaped charge jet armor penetration effect is purely kinetic in nature; the round has no explosive or incendiary effect on the armor.
Anti-tank warfare originated from the need to develop technology and tactics to destroy tanks during World War I. Since the Allies deployed the first tanks in 1916, the German Empire developed the first anti-tank weapons. The first developed anti-tank weapon was a scaled-up bolt-action rifle, the Mauser 1918 T-Gewehr, that fired a 13.2 mm cartridge with a solid bullet that could penetrate the thin armor of tanks at that time and destroy the engine or ricochet inside, killing occupants. Because tanks represent an enemy's strong force projection on land, military strategists have incorporated anti-tank warfare into the doctrine of nearly every combat service since. The most predominant anti-tank weapons at the start of World War II in 1939 included the tank-mounted gun, anti-tank guns and anti-tank grenades used by the infantry, and ground-attack aircraft.
Shoulder-fired missile, shoulder-launched missile or man-portable missile, among other variants, are common slang-terms to describe high-caliber shoulder-mounted weapons systems – that is: weapons firing large heavy projectiles ("missiles"), typically using the backblast principle, which are small enough to be carried by a single person and fired while held on one's shoulder. The word "missile" in this context is used in its original broad sense of a heavy projectile, and encompasses all shells and rockets, guided or unguided. A more formal variant is simply shoulder-fired weapons system and the like.
The Vietnam War involved the People's Army of Vietnam (PAVN) or North Vietnamese Army (NVA), National Liberation Front for South Vietnam (NLF) or Viet Cong (VC), and the armed forces of the People's Liberation Army (PLA), Army of the Republic of Vietnam (ARVN), United States Armed Forces, Republic of Korea Armed Forces, Armed Forces of the Philippines, Royal Thai Armed Forces, Australian Defence Force, and New Zealand Defence Force, with a variety of irregular troops.
A rifle grenade is a grenade that uses a rifle-based launcher to permit a longer effective range than would be possible if the grenade were thrown by hand.
The M72 LAW is a portable one-shot 66 mm (2.6 in) unguided anti-tank weapon. The solid rocket propulsion unit was developed in the newly-formed Rohm and Haas research laboratory at Redstone Arsenal in 1959, and the full system was designed by Paul V. Choate, Charles B. Weeks, Frank A. Spinale, et al. at the Hesse-Eastern Division of Norris Thermador. American production of the weapon began by Hesse-Eastern in 1963, and was terminated by 1983; currently it is produced by Nammo Raufoss AS in Norway and their subsidiary, Nammo Defense Systems in Arizona.
The Panzerfaust 3 is a modern semi-disposable recoilless anti-tank weapon, which was developed between 1978 and 1985 and first entered service with the Bundeswehr in 1987. It was first ordered in 1973 to provide West German infantry with an effective weapon against contemporary Soviet armor, thereby replacing West Germany's aging PzF 44 Light Lanze launchers and the heavy Carl Gustaf 84 mm anti-tank recoilless rifle manufactured in Sweden.
The Energa anti-tank rifle grenade is a rifle-launched anti-tank grenade that is propelled by a ballistite-filled blank cartridge. The name Energa comes from the firm in Liechtenstein that designed it, the Anstalt für die ENtwicklung von ERfindungen und Gewerblichen Anwendungen, based in Vaduz.
The M7 grenade launcher, formally rifle grenade launcher, M7, was a 22 mm rifle grenade launcher attachment for the M1 Garand rifle that saw widespread use throughout World War II and the Korean War. The M7 was a tube-shaped device, with one end slotting over the muzzle of the rifle and attaching to the bayonet mount, and the other end holding the grenade in place. Blank cartridges were loaded into the rifle prior to firing. When fired, the expanding gases generated by the cartridges propelled the grenade forward with considerable force. The M7 could fire grenades up to 200 metres, compared with the maximum of 30 metres achieved by a hand-thrown grenade.
The FGR-17 Viper was an American one-man disposable shoulder-fired antitank rocket, which was slated in the 1980s to be the replacement for the M72 LAW, but was canceled shortly after production began because of cost overruns and concerns about safety and capability.
Beyond-armour effect is a term coined by Försvarets Fabriksverk (FFV), a semi-governmental Swedish defense firm, while developing the AT4. From the 1980s this phrase was used in its brochures, press releases, weapon instruction manuals and other documentation to denote the post-penetration effect of the AT4's HEAT anti-armour warhead against the interior and occupants of armoured vehicles.
The Wasp 58 is a 58-mm rocket launcher antitank weapon developed in France in the late 1980s. The weapon was, originally, privately developed by the French firm Luchaire SA, subsidiary of GIAT.
The high–low system is a design of cannon and anti-tank warfare launcher using a smaller high-pressure chamber to store propellant. It allows a much larger projectile to be launched without the heavy equipment usually needed for large caliber weapons. When the propellant is ignited, the higher pressure gases are bled out through vents at reduced pressure to a much larger low pressure chamber to push a projectile forward. The high-low system allows the weight of the weapon and its ammunition to be reduced significantly. Production cost and time are drastically lower than for standard cannon or other small-arm weapon systems firing a projectile of the same size and weight. It has a far more efficient use of the propellant, unlike earlier recoilless weapons, where most of the propellant is expended to the rear of the weapon to counter the recoil of the projectile being fired.
An anti-tank grenade is a specialized hand-thrown grenade used to defeat armored targets. Although their inherently short range limits the usefulness of grenades, troops can lie in ambush or maneuver under cover to exploit the limited outward visibility of the crew in a target vehicle. Hand launched anti-tank grenades became redundant with the introduction of standoff rocket propelled grenades and man-portable anti-tank systems.
The AT4 is a Swedish 84 mm (3.31 in) unguided, man-portable, disposable, shoulder-fired recoilless anti-tank weapon manufactured by Saab Bofors Dynamics. The AT4 is not a rocket launcher strictly speaking, because the explosive warhead is not propelled by a rocket motor. Rather, it is a smooth-bore recoilless gun. Saab has had considerable sales success with the AT4, making it one of the most common light anti-tank weapons in the world. The M136 AT4 is a variant used by the United States Army.
Man-portable anti-tank systems are traditionally portable shoulder-launched projectile systems firing heavy shell-type projectiles, typically designed to combat protected targets, such as armoured vehicles, field fortifications and at times even low-flying aircraft.
The M9 rifle grenade was an American anti-tank rifle grenade used during World War II. The earlier-designed M10 grenade was too heavy to be fired an effective distance by a rifle; the M9 was conceived as a lighter version of that design.
