MBA GyroJet

This month we look on a classic that may have changed the world of firearms. When I first read about the Gyrojet, it was years ago in a James bond book. At the time I thought it was a "Q" device and didn't really exist. Years later, a Gyrojet pistol almost became my first firearm. I still regret not getting it. Read on and see why.

The MBA Gyrojet was conceived by Robert Mainhardt and Art Biehl. They formed MBAssociates or MBA. First off, The gyrojet is not a firearm in the conventional sense. It's ammo was a 13mm stainless steel armor piercing rocket. Later models were made in 12mm to comply with civilian guns having a max of .50 cal. Both pistol and carbine versions were available in different finish/price levels.

The pistol (well use that for our purposes here) is about the same size as a Colt 45, but it is very light, about 22 oz.

When holding it, the stamped steel/alloy construction combined with all the vent holes make you feel as if this were a toy and incapable of holding up to the pressure of being a firearm. Well, you're right, because the Gyrojet isn't a firearm in the conventional sense.

When a conventional gun is fired, all the pressure from the exploding powder is held in the chamber/barrel. This pressure is what pushes the bullet forward and why as soon as a bullet leaves the barrel, it starts loosing velocity.

The Gyrojet round is pushed by burning solid rocket propellant that is contained within the projectile, so therefore all the pressure is contained by the "bullet" and not by the gun. This also means that muzzle velocity/energy sucks, about 860 ft/sec. Like most rockets however, the longer the burn, the faster the projectile goes. This means at about 100 yards, the velocity is screaming supposedly at 100 yards it is about 50% more powerful than the .45.

Loading/shooting the Gryojet is an experience. To load it, one slides the top cover of the receiver, pushed all 6 rounds in from the top and quickly slid the door shut again. there ew no magazine or feed lips like a semi auto, so all the rounds want to fly back in your face if you are not fast. For anyone familiar with the M-1 Garand, imagine trying to load it without the EN-Bloc clip to hold the bullets in place.

With rockets in place, the pistol is cocked for the first shot via a cocking lever that is pushed forward and down.

This lever is on the left side of the frame just above the trigger. The rocket leaving the barrel cocks the hammer for the subsequent shots. When the trigger is pulled, there is not the noticeable bang of a gun. The Gyrojet just makes a small crack then a hiss as the rocket goes off. Shake and open beer can to hear this noise.

Reports of the time show the gyrojet had some decent accuracy among those who tested (note: I have held these guns, but never fired one due to lack of 12/13mm rockets at my local Wal-Mart). Instead of conventional rifling,the Gyrojet used multiple angled exhaust ports to spin the projectile as it traveled thru the smooth barrel. this produced great accuracy, but it was also one of the downfalls of the design.

MBA originally produced this weapon for use in Vietnam, and that's where some of the downfalls were seen. Rocket fuel (solid type) didn't always like humid weather, so misfires or not getting a 100% burn was a problem, though an infrequent one. Another problem was the slight chance of fouling of the exhaust ports. Remember they provided the rifling, so a fouled port could cause a wobbling path and nasty accuracy problems. The biggest drawback was that the rocket burning could leave a trail back to the shooter. Not good in combat.

After a thousand or so were produced, it seemed that the world was happy to stick with gunpowder. The Gyrojet disappeared, but due to its mention in war games like "Delta Green" interest is picking up in the real thing.

Gyrojet pistols in plain black finish are going for about $650 to about $1,500 for the gold presentation model. Carbines are goin for between $900 and $1,700. Last time I found ammo, it was in 1999 for about 30 a box. I personally would not recommend firing one anyhow as with no support for the Gyrojet, I don't even know who would be qualified to see if it's safe to shoot. But, if you want a real neat piece of firearms history, this is a neat one to hang on the wall

Next month, back to real guns we can buy and shoot Shoot safe, Rich the Range master

more from http://www.deathwind.com/review_5.htm:
The author is unaware of any authorized use of Gyrojet rocket pistols by US military personnel in Viet Nam. At that time however, it was not too uncommon for officers, and occasionally enlisted men, to bring their personal side arms with them. Some Gyrojet rocket pistols came to Viet Nam in this manner. At least two are reported to have been used in there. One was carried by Army Lt. Douglas G. Magruder, who died there. In his returned personal effects, was his Mark II Gyrojet. It was engraved with his name. The second Gyrojet user survived. His name was David Kirschbaum and his full story is available on the Internet at http://www.classicfirearms.org. Portions of Kirschbaum’s story are excerpted below.

David Kirschbaum Speaks

As a Recon man I liked the weapon just fine: light, quiet, low-maintenance, and a hell of a punch. I lay beside a well-traveled trail ‘deep within enemy territory’ for most of a day waiting to shoot some poor suffering NVA bastard in the hip with it, but no one ever came.

Never did shoot anyone with it. It was not silent, not like the true silenced .22 Hi-standards we often carried. But it was quiet, made a sort of "Psssssst!" sound like air escaping from a truck tire, maybe a half-second long. People would hear it, look around curiously like ‘What the hell was that?’ and go about their business, because it didn't SOUND like a weapon, it didn't SOUND dangerous! (I fired it in camp several times, demonstrating it, never got any attention at all.)”

“It was fully weatherproof, gun and rockets. I lay besides an LZ one day, hiding, waiting for the rain to stop and choppers to come. When I got back to CCC, I checked the pistol: the barrel and cocking/firing mechanism had filled completely with sand and clay that had washed down the bank to where I was lying on my chest.
I figured what the hell, let's shoot it off to see if it'll push the mud out. (Not like a regular pistol, where a plugged barrel would probably explode.)”

“I fired it, wondering if the rocket would clear the barrel. I was surprised to see the firing mechanism actually work despite all the sand and clay! But the rocket didn't clear the barrel: it went "Pssssst!"

just like always, but jammed in the barrel.”

“I took the pistol to the latrine, washed it out in a stream of water to clear out the sand. I recocked it manually (the "hammer" was in front of the rocket), poked a stick down the barrel and knocked the jammed rocket loose (it had only moved a fraction of an inch, it hadn't even recocked the "hammer". Then I removed the expended rocket, let a new rocket move up into the firing position, closed it back up again, and fired off the next rocket (that had been soaking wet for a week or more). No problem, fired just fine.”

“The biggest problem was the feed design. The rockets all pushed down into the handgrip of the pistol against a spring and follower. Then, while holding that last rocket down, you slid forward this cover on the top of the "receiver" that held them all in place. Fine and dandy if you were going to just shoot them. But shame on you if you had a misfire (although I never did) or a jam (which I did, once, re above). You'd have to slide back that slide, meanwhile holding all the rockets down with your thumb, and then they'd all want to come springing out! The design really REALLY sucked. It should've had a magazine like a regular automatic, instead of everything being integral. Impossible to clear in combat, and a real PITA to reload too. Never the less, I liked the pistol just fine.”

Summary and Thanks

Considering the results of the recent Gyrojet rocket pistol tests, it is probably a good thing that few were actually taken to Viet Nam. Close range Gyrojet velocity/energy was sub-lethal and longer range accuracy was doubtful. Also, as David Kirschbaum noted, clearing a jam or reloading a Gyrojet pistol during a fire fight was impractical.

Thanks are due to Leonard Yates for supplying the picture of Lt. Douglas G. Magruder’s personal Gyrojet pistol and for permitting to publish it. Thanks also to the Web Master of the Classic Firearms site for allowing to publish excerpts from David Kirschbaum’s personal recollections of his experiences with a Gyrojet in Viet Nam.

I don't have a pistol, but I have a few Gyrojet flares and a launcher. I got to fire one in my survival training in the AF in the early 80's. Thought it was neat, then read about it in Nivens books. About 2 year ago I saw a launcher and a pack of 6 flares in an Army surplus store, and HAD TO HAVE IT. It now sits in my display case with my other memorabilia like my flight helmet, my 30 mm DU round from a Gau 8 and some 20mm practice rounds from an F4.

Those little things were handy as all get out, also useful as a firestarter in a survival situation. I had one of the comparitively rare double-barrelled versions, and carried it on and off for years. Never knew when I'd have to call attention to myself to a passing Jolly Green.

The things are now available in a slightly different form, including *bear bangers* for hopefully scaring away pesky bruins, as well as red, white or green flares for distress signalling.

The price of the newer plastic-bodied flares is a little easier to take than the old MBA aluminum ones, too.

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