The grainy videos hinted at a lethal form of surprise.

Two RKG-3 hand grenades wobbled through the air, thrown simultaneously by a pair of young Iraqi men. The small chute on each grenade opened, stabilizing the ordnance in flight and orienting their explosive shaped charges toward their targets. The men had thrown them ahead of a vehicle in a passing American convoy, leading the target by putting the grenade where they expected the vehicle to be in a moment. The vehicle and one of the grenades met. An explosion flashed on the screen.

This kind of attack occurred many times in Iraq, often with fatal consequences. Yet the weapon and tactic were not often discussed publicly. Relatively small and easily concealed, the RKG-3 is a peculiar type of grenade, another relic of the Soviet arms-design bureaus that found fresh uses after the Soviet Union collapsed. Once considered an obsolete weapon with a narrow use, it was largely ignored by Western intelligence services before the American-led invasion of Iraq in 2003. And yet it mattered to troops exposed to its dangers, and it matters now to a richer and fuller account of the Iraq war.

Improvised weapons are being used today in other insurgencies, notably by rebels in Syria fighting against President Bashar al-Assad’s forces. (There is already evidence of technology migration from Iraq to Syria via the Lebanese militia group Hezbollah.) The brutal effectiveness of some of these weapons makes it likely that the United States will face them on other battlefields as well, and should become part of the standard baseline threat considered by military planners well into the future.

So how did this weapon find new life among insurgent forces in the 21st century? And where did they come from?

Answers to these and many other questions about how insurgents fought in Iraq can be deduced from dozens of declassified reports obtained through the Freedom of Information Act by Matthew Schroeder, a researcher at the Federation of American Scientists and the Small Arms Survey. As part of a joint research project on illicit weapons, Mr. Schroeder acquired battlefield reports detailing weapons caches recovered by the American military in and around Baghdad from 2007 to 2010. He generously shared these documents with At War.









Mr. Schroeder’s documents detail what was found in insurgent stockpiles, and when combined with video of insurgent tactics, they underscore two things that many American veterans of the war remember keenly. First, that years of brutal fighting had taught Iraqi fighters which weapons were most effective against their heavily-armored, conventional American foes. And second, that the war as experienced by combatants on the ground was for more complex and presented more forms of lethality than the conventional wisdom has allowed.

The Origins and Nature of Insurgent Arms Supplies

Like many of his regional contemporaries, Saddam Hussein used Iraq’s oil wealth to acquire huge quantities of weapons during his long rule. In the early 1970s, the Soviet Union and its Eastern bloc partners provided most of Iraq’s weapons, part of the Kremlin’s cold war engagement in the region. During its war against Iran in the 1980s, Iraq acquired more stockpiles and developed its own weapons industry. Many of these weapons became available to insurgents with the fall of Baghdad in 2003.

The documents obtained by Mr. Schroeder, known as “storyboards,” also show that Iraq’s insurgents drew their weapons from more than their country’s pre-invasion stockpile. Some were American weapons brought into the country after the invasion, and then acquired by looting storehouses or from destroyed American vehicles, or perhaps the remains of slain troops.

Several storyboards show newly-manufactured arms from Iran, which provided weapons with lot numbers indicating manufacture as recent as 2008 – literally war-time production for a nation already awash in arms.

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Taken together, the storyboards offer a glimpse of what military analysts might call the insurgents’ order of battle. They detail weapons common to armed conflict worldwide: AKM-variant assault rifles, as the basic shoulder-fired arm; PK copies for belt-fed automatic fire; RPG-7s for anti-armor fire; and a small number of fragmentation hand grenades. All of these had been manufactured in a variety of countries. Through trial and error, Iraq’s fighters also acquired and put to use a variety of other weapons, some familiar to Western militaries. Still others were improvised, mixing weapons parts with non-military components.

Some weapons were noticeably absent, perhaps because Iraqi fighters learned they were not well-suited to their insurgency. Heavy mortars are perhaps the best example. American counter-battery fire could quickly and accurately return fire against insurgent mortar teams using large-caliber, hard-to-move tubes. This meant that items like 240–millimeter mortars and recoilless rifles were lightly used. American forces found tens of thousands of 73-millimeter recoilless rifle rounds for the SPG-9 weapons system in Iraqi caches, but rarely faced the weapons in combat. They weren’t even well-suited as donor charges in improvised explosive devices.

American soldiers discovered weapons caches in a variety of ways, the storyboards show. Intelligence tips from Iraqi citizens led to many; others were found during raids or sweeps for suspected insurgent leaders. Working dogs accompanying foot patrols sometimes picked up the scents of buried explosives. Each of these discoveries pulled a quantity of weapons out of circulation. Often these finds were only a temporary disruption. Mr. Hussein’s old stockpiles had been vast. Insurgent sources for more weapons never seemed to dry up.

We have broken down the storyboards into two categories. Today we’ll look at some of the conventional weapons and tactics. Tomorrow, we’ll explore the unconventional or improvised, and discuss why they matter — possibly more than the conventional ones.

The RKG-3

Designed by the Soviets shortly after World War II, the RKG-3 HEAT hand grenade largely caught foreign troops off-guard after the 2003 invasion. Originally intended as a last-resort defensive weapon for infantry troops fighting off tanks in open terrain, the Iraqi insurgents learned to use the grenade in a particularly effective manner against convoys.

In earlier wars, “wolf packs” of multiple attack submarines picked off lagging ships with torpedo strikes. In Iraq, insurgent forces learned to do much the same with American armored vehicles using this grenade. When coalition forces drove through crowds of Iraqis, often an ambush was waiting for the tail vehicle. Easily concealed under the robes of a dishdasha, the RKG-3 could be used at the last moment and thrown overhand at very short range – close enough to give American forces no time to return fire. Unlike common antipersonnel hand grenades, the RKG-3 is an anti-armor weapon. It could blow silver dollar-sized holes through both sides of an armored Humvee – killing people within and destroying the truck.

Western intelligence had disregarded the RKG-3 for a half-century until its reemergence in Iraq. When the Red Army fielded the first rocket-propelled grenades in the 1950s, the RKG-3 became functionally obsolete – or so it seemed. Rocket motors allowed soldiers to maintain a standoff of several hundred yards and deliver a shaped charge inside a fast-flying projectile, thus increasing the likelihood a shooter would survive the engagement with an enemy tank. But in Iraq, insurgents firing rocket-propelled grenades at American vehicles exposed themselves and were routinely killed by soldiers using turret machine guns. The trick became to attack with the target in close – thus preventing the return fire. The RKG-3 was well-suited for this. Mr. Hussein had bought thousands made in the Soviet Union, Yugoslavia, Romania and China. Insurgents spread them all over Iraq.

Rockets and Mortars



While roadside bombs caused the most casualties to foreign troops in Iraq, Mr. Hussein’s stockpiles of rockets and mortars gave them ways to carry out stand-off, or “indirect” attacks on fixed positions like patrol bases. Quick to set up, insurgents often fired these weapons with no direct line of sight to their targets.

Fortunately for the targeted troops, enemy mortar and rocket crews sometimes misapplied nose fuzes, preventing weapons from detonating on impact. Conventional wisdom among American troops held that the insurgent crews lacked the training to select the proper fuzes — but they sometimes got it right. And around Baghdad, Shiite fighting groups had access to newly made Iranian ordnance, as well as training on proper fuze selection.

One weapon found repeatedly is the Type 63, a Chinese 107-millimeter artillery rocket uniquely suited for guerrilla warfare. Unlike the longer 122-millimeter rockets of the “Grad” series, the Type 63 is self-stabilizing and thus can be fired from a simple ramp of dirt or rocks, a tactic documented by At War in Afghanistan. Because it does not need a large rocket launcher — which can be hard to hide and easily destroyed from the air — the Type 63 is an ideal guerrilla weapon.

Iranian copies of the Type 63, called the Fajr-1, were commonly found in caches too.

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Insurgents sometimes used the Fajr-1’s rocket-motor section to propel IRAMs, or improvised rocket assisted munitions, used in Iraq, and recently in Syria.

Insurgents built crude improvised launchers for all types of rockets, but one storyboard shows a more complicated covert system – a passenger van modified to fire 57-millimeter rockets.

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Designated the S-5, and roughly analogous to their American 2.75-inch counterparts, these rockets were originally designed to be fired from aircraft against ground targets.

As with any indirect system, a high volume of fire was required to ensure damage to a target. That required large quantities of supplies. Some caches had hundreds of mortar rounds in a single location, and others had similar numbers combined with rockets, RPGs, C4 and other I.E.D. supplies.

The Outliers

The storyboards suggest that insurgents were not in wide possession of one widely feared direct-fire weapon: the SA-7 Grail, a guided, shoulder-fired anti-aircraft missile. The storyboards show only one complete weapon system being recovered. (Below, part of the storyboard. Full storyboard here.)







Other reports show recoveries of partial systems. The systems comprise three separate pieces — missile tube, gripstock, and thermal battery — and are not usable unless complete.

Americans also recovered the gripstock for a Chinese surface-to-air missile system. A diplomatic cable released by the anti-secrecy group WikiLeaks also shows the 2008 discovery of two Chinese systems in Iraq.

Sniper rifles were feared on the battlefield, but weren’t often recovered in caches. Nor were antitank guided missiles. Other small arms found in just a few instances were the HK MP-5, a submachine gun, and the RPK machine gun.





Taken together, the conventional weapons provided insurgents with a potent arsenal to attack coalition forces. And attack they did, as coalition troops were slow to secure weapons caches, leaving the country awash in arms.

John Ismay is a former U.S. Navy Explosive Ordnance Disposal officer who served in Iraq in 2007, and is now a member of Columbia Journalism School’s class of 2014. Follow him on Twitter @johnismay and on his blog johnismay.com.