Rocket Ammo — Firing a Gyrojet Pistol and Carbine

Once upon a time, the Gyrojet was invented; a gun which fired self-propelled rockets instead of simply flinging projectiles. And… it failed. But why?

Cost was certainly one large factor. Not only were the guns costly, the ammo was much more expensive than other ammunition.

The guns were apparently priced high purely for profit reasons, because they are actually simpler than conventional firearms, and don’t even have to be as strong, because they are not tasked with containing the extreme pressures of conventional ammo. Instead, they simply ignite each round and then serve as a launch tube to direct its flight.

The projectiles are quite light, with an unfired 13mm (roughly .50 cal) Gyrojet round weighing just 240 grains — the weight of a 44 Magnum hunting bullet. Remember, the Gyrojet “cartridge” also contains the propellant, which will burn off in flight, further reducing its weight before impact to about 209 grains.

Unlike conventional bullets, which begin to slow and fall towards earth as soon as they exit the muzzle, Gyrojet ammo actually accelerates as it flies downrange.

In the video, a Gyrojet pistol and carbine are both fired. The first is from the pistol, and it fails. I mean, it does fly, but the primer ruptures and it flies in an unintended way, hitting higher than expected and having to be recovered with a metal detector days later.

The second round buried itself into a Kevlar vest… something even a 45 ACP isn’t apt to do. The third round hit their watermelon target, and the fourth was stopped by a fiberglass panel.

Somewhere, I have some ammo for these things. I probably need to sell it off…

Russ Chastain

Editor & Contributing Writer Russ Chastain is a lifelong hunter and shooter who has spent his life learning about hunting, shooting, guns, ammunition, gunsmithing, reloading, and bullet casting. He started toting his own gun in the woods at age nine and he's pursued deer with rifles since 1982, so his hunting knowledge has been growing for more than three and a half decades. His desire and ability to share this knowledge with others has also grown, and Russ has been professionally writing and editing original hunting & shooting content since 1998. Russ Chastain has a passion for sharing accurate, honest, interesting hunting & shooting knowledge and stories with people of all skill levels.