“Since a regulation-size football weighs 14 ounces, it was considered feasible to make a shaped charge grenade within this weight limitation. In addition, most US troops are familiar with throwing footballs,” according to the Army’s test report for the weapon.
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Footballs fly through the air because there is an even distribution of weight surrounding the hollow inside of the ball. But 14 ounces of explosives tended to make the trajectory of the Nerf grenade “unpredictable,” according to the test report.
https://www.military.com/history/armys-anti-armor-football-grenade-did-not-work-envisioned.html
You might be able to find more about it elsewhere, though, this is just the short article I got it from.
Ok, I will read more thanks. I already found a loosely sourced article here..
I suppose I had overlooked what should have been obvious, especially since I already mentioned MPIM (Multi-Purpose Individual Munition program, a program in the 1980s looking for ways to launch munitions without backblast), but the football grenade appears to have been spawned from looking for a way for soldiers in urban areas to attack armor from inside buildings and to reduce how visible they were during attack. I’d still rather have a way to launch it though (PIAT gang 4 life).
Looks like possibly only one was made, so I guess not a super successful program, but I’m genuinely interested to see if there’s any more deep lore on it.