Even now, nearly sixty years after its invention, the RPG continues to see service worldwide.

One of the most iconic weapons of war ever made arose from Soviet experiences in World War II, when Red Army infantry had no answer to invading German panzers. Simple and effective, the broomlike RPG-7 became one of the most effective antitank weapons of the postwar period. Widely exported, the “RPG” became a symbol of revolution and terror, fielded by armies and guerrillas from Berlin to Phnom Penh.

The Soviet Union in World War II had a serious problem: it had no effective handheld antitank weapon for its infantry. The Soviet Army had hundreds of infantry divisions fielding as many as a million infantrymen at any one time, but individual grunts had little to defend themselves with from German armor such as the Panzerkampfwagen II and III.

The development of shaped-charge antitank weapons dramatically improved the infantry’s odds of stopping an armored attack. The principle of the shaped charge was first demonstrated by Charles Munroe, a professor at the U.S. Naval Academy, in 1888. A cone-shaped cavity is placed against a slab of metal, or tank armor, and an explosive charge is detonated behind it. The cavity channels the force of the explosion through the cone to the tip. This enables a shaped charge warhead to penetrate armor up to seven times the diameter of the charge.

Shaped charges developed for military use became known as high-explosive antitank (HEAT) warheads. The great advantage of HEAT warheads was that unlike traditional armor piercing antitank rounds, they did not rely upon projectile velocity and density to penetrate armor. A HEAT charge lobbed at a tank by hand had the same effectiveness as one fired from a high-velocity tank gun.

The German Army was the first to field an effective, man-portable antitank weapon, the Panzerfaust. The Panzerfaust was basically a stick with a shaped-charge warhead launched by a black-powder explosion, and yet early versions could penetrate up to 140 millimeters of armor. The final version, the Panzerfaust 250, featured a reloadable launch tube and a pistol grip.

The Soviets took the Panzerfaust 250 and developed their own version, the Ruchnoy Protivotankovyy Granatomet-2, or RPG-2. Commonly mistranslated as “rocket-propelled grenade,” it actually means “handheld antitank grenade launcher.” The RPG-2 entered service with the Soviet Army in 1949. Rocket-propelled, it had a range of 150 meters and could penetrate 180 millimeters of armor. This made it possible for the rawest of recruits from the motherland to destroy the latest NATO tanks, including the American M26 Pershing and British Centurion, with ease. The RPG-2 was widely exported abroad, and armed both North Vietnamese Army and Viet Cong units during the Vietnam War.

The RPG-2 was followed up by an improved version, the RPG-7, in 1961. The RPG-7 had a slightly better range: two hundred meters versus 150 meters. Unlike the RPG-2, which had simple iron sights, the new version had the PGO-7 telescopic sight, which had 2.8× magnification, an illuminated reticle, and a sight reticle to assist in ranging and aiming at moving targets. A cone-shaped blast deflector was added to the rear of the launch tube and a foregrip was added for increased stability. The PG-7 HEAT round could now penetrate 260 millimeters of tank armor, increased to three hundred millimeters with the improved PG-7M warhead.

The RPG-7 enhanced the portable antitank weapon concept in other ways. The RPG-7D, designed for paratroopers, broke down into two pieces to make it easier to air transport. New grenades included the OG-7 high explosive round, useful for unarmored targets and enemy infantry. The advent of so-called explosive reactive armor, which uses boxes of explosives reduce the effectiveness of HEAT rounds, caused the Soviets to develop the PG-7R tandem HEAT round. The longer, bulkier grenade featured not one but two explosive charges, the first to neutralize reactive armor and the second to detonate against the armored vehicle itself.

The RPG-7 was issued at the squad level in the Soviet Army and the rest of the Warsaw Pact nations, meaning every squad of six to nine infantry had one dedicated RPG gunner and his assistant. This meant that a Warsaw Pact infantry company could mass up to nine RPGs to defend its sector at close range, in addition to antitank guided missiles.

Thanks the Soviet Union’s generous support of guerrillas and revolutionary movements worldwide, RPGs were also used in Central America, Southeast Asia, conflicts throughout Africa and the Middle East. RPGs were even used by the German Red Army Faction in an attempt to assassinate an American general, and by the Irish Republican Army against the British Army in Northern Ireland. In 1993, the RPG-7 was used to shoot down Super 64, a Black Hawk helicopter operated by the 160th Special Operations Aviation Regiment, triggering the now-infamous Battle of Mogadishu. One of the most famous users of the RPG was the original Afghan mujahideen, who used them in great numbers against Soviet occupation forces from 1980 to 1988.

Even now, nearly sixty years after its invention, the RPG continues to see service worldwide. RPGs were a persistent threat in the Iraq War, first arming the Iraqi Army and then anti-government and anti-Coalition forces. Following in the footsteps of the mujahideen, the Taliban field the RPG in prodigious numbers; as author Gordon Rottman has pointed out, seven out of eight U.S. Army helicopters shot down in Afghanistan between 2001 and 2009 were downed with RPGs. RPGs are active with Hamas and Hezbollah, can be found among nearly all sides in the Syrian Civil War and are used by fighters loyal to the Islamic State.

The RPG-7 was replaced by a further improved model, the RPG-16, in the 1970s. The most recent RPG, the RPG-29, was adopted in the waning days of the Soviet Union in 1991 and is in frontline service with Russian Ground Forces today. The RPG-29’s standard antitank round is a tandem warhead HEAT round, with thermobaric fuel-air warheads available for use against bunkers and fortifications. The RPG-29 has achieved penetration against modern Western tanks in three incidents, all in Iraq, against Abrams tanks (twice) and a Challenger 2 tank.

Soviet experiences in World War II made effective antitank weapons an imperative at all levels, all the way down to the infantry squad. While many of the Soviet Union’s and later Russia’s weapons were a generation behind their Western counterparts, that was certainly not the case in handheld antitank weapons. As tensions between the United States, NATO and Russia increase, it planners should keep in mind that even Russian light infantry can be extremely dangerous to armor.

Kyle Mizokami is a defense and national-security writer based in San Francisco who has appeared in the Diplomat, Foreign Policy, War is Boring and the Daily Beast. In 2009 he cofounded the defense and security blog Japan Security Watch. You can follow him on Twitter: @KyleMizokami.

This article originally appeared in June 2017.

Image: Department of Defense

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