The Army Tried To Turn Nerf Footballs Into Hand Grenades

The goal of the “football device” was to give soldiers a way to take out tanks at close range in a package the Army hoped would be instinctual to use.

byJoseph Trevithick|
U.S. Army photo


Few things are as quintessentially American as football and most people in this country have probably played it in some form at least once in their life. This was what the U.S. Army was banking on when it developed an anti-tank grenade using an explosive charge jammed into a hollowed-out Nerf football in the early 1970s.

The Army's Land Warfare Laboratory (LWL) at Aberdeen Proving Ground in Maryland concocted the "football device," something I wrote about briefly years ago now, as part of a broader effort to develop a hand-thrown anti-tank weapon of some kind that began in July 1973. The Army had originally established LWL in 1962 to develop, test, and evaluate any and all weapons or other technology that might be applicable to counter-insurgency campaigns, a type of warfare that was emerging around the world at the time. This included in various countries in Southeast Asia, such as South Vietnam and Thailand, where the United States was already becoming increasingly embroiled at that time. 

In 1970, LWL was renamed the Land Warfare Laboratory, a switch that kept its acronym intact, and it began exploring systems that be might useful to a broader set of conflict types. One of these efforts was the anti-tank grenade project, a requirement driven by concerns about the utility of existing infantry anti-armor capabilities, especially in an urban environment, such as the ones the U.S. military expected to be a primary setting for any major conflict against the Soviets in Europe.

"Current standard US Army antitank weapons have been designed to provide maximum practical stand-off range," a 1974 final test report on the football grenade, as well as the other types LWL evaluated, explained. The primary infantry anti-tank weapons in Army service at the time were the BGM-71 TOW and FGM-77 Dragon anti-tank guided missiles and variants of the M72 Light Anti-Tank Weapon (LAW), a shoulder-fired rocket launcher.

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The issue with these weapons, as LWL's report noted, was that firing them would often reveal the location of the shooter. The Dragon was a particularly notorious offender in this regard, putting the person that fired it immediately at risk and making it difficult for them to quickly re-engage if the first shot missed. In addition, the missiles, as well as the M72s, could not be employed safely from within confined spaces, such as from the inside of a building. 

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On top of that, to protect those firing them from getting caught in the blast, these missiles and rockets had to travel certain minimum distances before arming themselves. In a cramped urban setting with fighting that could be in very close quarters, this would also have limited the ability of troops to employ these weapons. 

At the time, the Army trained troops to engage heavily armored vehicles under these conditions using a variety of improvised means, including ponchos filled with oil and gasoline and explosive charges packed into empty ammunition cans. They were to, whenever possible, exploit the lack of situational awareness that armored vehicles crews have when they are "buttoned-up" inside with all their hatches closed. 

A low-quality scan of a page from a comic book-style Army manual from 1972 describing improved explosive means for damaging tanks in close quarters., US Army via FOIA

This is very much how the service had done things since World War II. Steven Spielberg's famous 1998 film about that war, Saving Private Ryan, notably includes the use of improvised "sticky bombs," consisting of socks full of explosives dipped in thick oil, against Nazi tanks in its climactic final battle.

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"A hand-thrown short-range device appeared to overcome the deficiencies of standard weapons in an urban environment," LWL's 1974 report said. "A hand deployed device which will give the infantryman in urban warfare the capability to disable a 'buttoned-up' tank is desired."

LWL decided to focus on hand-thrown weapons containing a shaped charge, a warhead design commonly used in anti-tank missiles and rockets. A shaped charge, also known as a hollow charge, features a large open cavity inside between the main explosive charge and the front of the projectile. An inverted cone-shaped metal liner, typically made copper, is inserted into the explosive charge. When the charge goes off, it expands outward, turning the liner into a high-speed metal dart of sorts that then punches through the target. 

The video below shows the basic function of such a shaped charge, using a high-explosive anti-tank shell as an example.

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This is a technology that dates back to the late 19th century and is still in use today. It works, but its effect is greatly diminished if the full force of the resulting projectile isn't directed at the target at an optimal distance or angle. Countries around the world have added a wide array of spaced armor, slats and nets, and even small bricks of explosives to the side of armored vehicles to prevent shaped charge weapons from detonating as intended.

LWL then determined that the optimal methods of attack for a hand-thrown anti-tank grenade using a shaped charge at close range were dropping it out of a window on top of the vehicle, lobbing it on top of the vehicle from cover, or otherwise trying to hit the top of the vehicle from the furthest distance away possible. Typically, the top of the turret or the rear hull of a tank or another heavily armored vehicle is where its armor is the weakest. Furthermore, killing crew members inside or severely damaging or destroying the engine compartment could be enough to achieve a mission kill.

It's interesting to note that when LWL started its work on developing a weapon that would meet these requirements and be usable in one or more of those scenarios, many other countries, including America's European allies and the Soviet Union, had already fielded anti-tank grenades decades earlier. By the 1970s, some nations, especially the Soviets and their allies, were still using them. 

Personnel at the Army laboratory identified multiple foreign types that informed its work, primarily so-called "potato masher" grenade designs with stick-like handles for throwing. Anti-tank versions of these grenades almost universally had some kind of retarding device, such as cloth strips or even a small parachute, which would help stabilize the grenade. The idea is that these features would help the grenades fall near vertically on top of a vehicle to maximize the effect of their shaped charge warheads. Rather than timed fuzes found on typical hand grenades, these hand-thrown weapons often had impact fuzes that would only go off when they struck something.

A Cold War-era Polish-made Soviet-designed "potato masher" style RPG-43 anti-tank grenade. When thrown, the cone at the base of the handle would drop off, extending two cloth strips in the process to stabilize the grenade., International Military Antiques

Not surprisingly, LWL crafted two of its own potato masher grenade designs, including one with a magnet at the front to help it stick to the target before going off. It also built two experimental dart-shaped designs, one with fins and another with a cowling of some kind, both designed to stabilize them after they were thrown. Sadly, there do not appear to be any pictures readily available of either of these apparent anti-tank lawn darts. The basic idea sounds similar in some respects to the British World War II-era No. 68 anti-tank grenade. It also sounds broadly reminiscent of the U.S. Civil War-era Ketchum hand grenade, a Union weapon that featured an egg-shaped explosive body with a wooden tail fin and that has its own visual similarities to a modern vortex football.

A deactivated No. 68 anti-tank grenade., Arundel Militaria
A Ketchum hand grenade., Wilson’s Creek National Battlefield

And then there was the football device. "Since a regulation size football weighs 14 ounces, it was considered feasible to make a shaped charge grenade within this weight limitation," according to LWL's 1974 report. "In addition, most US troops are familiar with throwing footballs."

LWL made at least one experimental model using a hollowed-out Nerf football with a metallic container and a conical fin at one end that held the shaped charge inserted in the middle, but it's not clear if this was a functional prototype. Parker Brothers had launched its brand of now-iconic foam balls in 1969, but there is no indication that they were in any way directly involved in the project. Nerf has since gone on to become a cultural institution better known for its foam dart-shooting guns.

The football device., US Army

In a way, this idea makes perfect sense. Footballs are intended to be thrown across relatively long distances in a manner that stabilizes them in flight making them more accurate. The Army says that it expects an average soldier to be able to throw a standard fragmentation grenade out to a distance of 35 meters, or just under 115 feet, while standing. NFL quarterbacks routinely demonstrate their ability to throw footballs much further than that. It was not necessarily out of the realm of reason to believe average soldiers, while not professional football players, would still be able to get more range and accuracy out of a football-shaped grenade.

It's not the first time the Army had used this kind of logic, either. During World War II, the service, together with the Office of Strategic Services, the predecessor of the Central Intelligence Agency, had experimented with fragmentation grenades that were the exact same size and weight as regulation baseballs for similar reasons. Those grenades, designated the T-13 and nicknamed the "Beano," never entered service owing to their use of a dangerously sensitive impact fuze that killed two people and injured 44 others in the course of testing. 

A cutaway schematic of the baseball-shaped T-13 Beano grenade., US Army

They did, however, inform the design of the spherical hand grenades that the Army subsequently adopted to replace its French-derived World War I-era Mk 2 "pineapple" grenades. To this day, the service uses a similar design with a slightly more ovular shape as its standard fragmentation grenade.

It's not clear how many football grenades LWL made in total and what the ultimate configuration might have been, but the design never came close to being field operationally. As perfect as the idea probably sounded in the heads of the engineers who came up with it, it's probably just as obvious to anyone who has ever seen a football bounce after hitting something as to why it didn't work. It proved to be virtually impossible to ensure the grenade's shaped charge detonated at the correct moment to reliably penetrate any armor. The weight distribution of the Army's "device," unlike a regulation football, which is uniformly hollow inside, made it unstable in flight, too.

Here is how LWL's 1974 report explained the results of the tests:

Test on the football shape indicated it also had a low tendency of nose-on impact. In addition, both the spring wire and soft aluminum placed on the nose to cause the "football" to rotate upon impact, so the nose would be perpendicular to the tank surface, did not work as envisioned. The "football" would bounce away before the nose rotated any significant amount. In addition, the "football" never attained a stable trajectory. This was apparently caused by the mass of the grenade type "football" being near the longitudinal axis while a real football has all its weight in the "skin." The football shape was not considered practical for further development.

LWL testing also showed that none of the anti-tank grenades it developed, including the football type, could be practically employed at distances over 10 meters, or just under 33 feet. One has to imagine that it could not have been easy to ensure that the football grenade would come down on a target, at all, and, even if it had worked as intended, it seems unlikely that drilling it into the side of a tank or other heavy armored vehicle would have produced the desired result.

The 1974 final report's one-sentence conclusion on the entire project, which cost the Army a paltry $12,167, is curt. "The lightweight (1 1/2-lb.) 'potato masher' grenade with parachute showed some promise that it could be developed into a useful antitank weapon if a 10 meter average range could be tolerated."

The Army shuttered LWL entirely the same month the report came out, amid post-Vietnam War drawdowns, and ultimately decided not to pursue any of the designs, or an anti-tank grenade of any kind. It, along with the U.S. Marine Corps, also passed on the curious spherical-shaped Rifleman’s Assault Weapon (RAW), a rocket-propelled weapon intended to be fired from a standard M16 rifle. That weapon had come from the Brunswick Corporation, a major manufacturing company that had gotten its start making bowling balls and pool tables.

An M16A1 rifle equipped with a launcher for the Rifleman's Assault Weapon. One of the rocket-propelled weapons is seen loaded underneath the muzzle., DOD

The service ultimately fielded high-explosive dual-purpose rounds, which have some anti-armor capability, for its 40mm grenade launchers. Versions of the M72, as well as its successor in Army service, the M136, have since been developed with features allowing them to be safely fired from enclosed spaces.

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In contrast, the Soviets continued to field anti-tank grenades, as well as export them. Insurgents were still using 1950s-era RKG-3s, a potato masher anti-tank grenade with a small parachute in the handle, against American forces in Iraq to significant effect in the 2000s, especially against lightly armored Humvees and even early Mine-Resistant Ambush Protected (MRAP) vehicles. In 2009, the U.S. Department of the Treasury sanctioned one Iraqi militant group, Jaysh Rijal al-Tariq al-Naqshabandi, specifically citing its use of the RKG-3, among other things. 

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It's not clear what happened to any examples of the football device that LWL built, but anyone who's ever played with a Nerf ball knows that they're not exactly designed to stand the test of time. The author knows of only one picture to exist of a prototype, which is seen in this story, but there is always the hope that more are hiding, yet to be discovered, in an archive or attic somewhere.

The idea of a literal football grenade has appeared in popular culture at least once, 25 years after the LWL's real-life project ended, in the 1999 film Three Kings, a sort of action heist movie with the aftermath of the first Gulf War as a backdrop. Spike Jonze's character uses electrical tape to tie C4 explosive charges and detonators to brightly-colored Nerf-like footballs out of boredom and Ice Cube's character eventually uses one to blow up a helicopter toward the end of the film.

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All in all, the football grenade may not have worked out, but it certainly one of, if not the most distinctly American weapons to ever be developed on any level.

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