Myths and Facts:


A very common myth is that the gyrojets smoked, thus revealing the shooters position. Gyrojets DO NOT SMOKE, the propellant was a single 3 gram double base nitroglycerine / nitrocellulose grain and is commonly known today as “Smokeless” powder. The only exhaust products are nitrogen gas, carbon dioxide gas, heat and water vapor. On a cold day the water vapor will condense and produce a CONTRAIL, exactly like a jet airplane. This is the origin of the smoking myth. As a footnote, under the cold and dry conditions that a contrail would occur a normal firearm will also produce a small cloud of condensation at the muzzle (similar to an automotive exhaust) also revealing the shooters position. It is the SAME PROPELLANT, if someone is shooting back you have the same problem…...


There are a wide range of reports of power. This, I attribute to the fact a Gyrojet is a rocket and performs as such, starting slow and achieving maximum velocity at fuel burnout, which in the case of the standard 13mm Gyrojet was at approximately 70 yards from the muzzle. The projectile has been known to not travel at all in the event of a barrel blockage, harmlessly venting its propellant out the barrel vents. However just like a compressed air bottle with a valve break is reluctant to move at first, once it starts forward motion is near impossible to stop. The now infamous plastic bucket experiment serves to show how quickly it actually does gain velocity. It’s a good thing that wasn’t a catcher’s mit…...


According to MBA at fuel burnout the average velocity was about 1250 fps for the standard 185 grain Gyrojet and it develops 700 ft/lbs energy. This is very impressive considering a standard loading of a .45ACP is in the neighborhood of 850 fps with 370 ft/lbs at the muzzle. However this is somewhat like comparing apples and oranges because the Gyrojet is gaining velocity until fuel burnout while the standard bullet is loosing velocity from the instant it exits the muzzle. This would make the Gyrojet over TWICE the MUZZLE energy of the .45ACP AT 70 YARDS . The Gyrojet projectile is far more subject to deflection at close ranges while moving slower and up close the .45ACP surely would have more performance than the Gyrojets. Once it gets moving a little it is harder to deflect and increasingly gets more impressive ballistics.


Considering that from a practical standpoint the use of a pistol or a rifle launcher doesn’t particularly matter to a rocket cartridge on either accuracy or velocity. By its very nature the Gyrojet was not going to perform well at very close ranges, it is my opinion if it had been marketed only as a rifle it would have had fewer problems. It is the PERCEPTION that a pistol is only used at close range and a rifle only long range that was one of the contributing factors to its downfall.


Accuracy was definitely a problem as discussed elsewhere on this site, however under the conditions of hand selected ammunition the accuracy proved to actually be quite impressive. The accuracy issue is in my opinion is at least a two point issue, first the ammunition manufacturing was entirely by hand on small presses and secondly there was obviously a quality control issue. The “DeathWind Gyrojet” design addresses part of the accuracy problem.


Of course the minor fact that in 1968 the Federal Government forbade the further manufacture of the 13mm (over .50”) ammunition has to be the major factor. The attempt to retool to 12mm and totally drop all support for the 13mm product that was already in existence was the end of the line for the Gyrojet, they just couldn’t recover. All per 1968 production is now considered to be “Curios and Relics” by BATF.


The Gyrojet pistols did see limited combat testing in Vietnam , however to date I can find no evidence of anyone then or since actually being shot by one. The liberals would love this one, a gun that has been in use over 45 years and never harmed anyone…….. and to think they banned it as being too dangerous……….


For the benefit of those folks that have never fired one of these puppies they are one of the most unique and fun weapons I have ever had the pleasure to fire. They actually feel more like toys than real firearms. I will attempt to describe a first time event:

When you pull the trigger there is a click of the hammer hitting, a faint pop of the primer and a muffled whoosh sound. If it is a rifle you will feel a warm damp puff of air on your hand that is on the forend as the rocket passes and suddenly you see and hear the impact of the rocket on the target. It is very similar to shooting a suppressed firearm. Until you get used to it, it is only too easy to flinch when you feel the warm air in the expectation of massive recoil, but there is none. There is no deafening noise and pounding recoil that we have learned to enjoy……. did it really go off? All of the noise and damage is downrange, somehow you feel cheated…… No Pain, No Gain, right……. There is so little pressure and recoil at the launcher that MBA actually used glass tubes in some of their test fixtures so they could watch the launch. Nowadays the pain is in your wallet with a single round of ammunition costing a minimum of $30.00 to $50.00, that is, IF you can even find them. They are especially fun to shoot into water because at close range you only hear a whomp sound as it enters the water and you can actually see a trail of bubbles going thru the water, just too cool…... This is some of why I have the quest to develop the “DeathWind Gyrojet”.


It is my belief that in life you must pay your dues. Since very little in life is original, only improved versions of older ideas, to that end I am obliged to recognize and credit the people and events who have come before that have made this concept possible.

Heron of Alexandria developed the first steam ball “reaction engine”. The origin of the simplest rocket as we know it comes from the invention of black powder and the use of it to propel “flaming arrows” around 1232 AD in China .

There has been a steady enhancement of rocket designs since around 1800. There are several documented small to medium rocket weapon designs to name just a few such as Congreve Rocket System in 1809, Voss Musket Rocket in 1834, the Hunt Rocket Ball in 1848, Hale 24 Pound Rocket in 1884 (first to use spin stabilization), Goddard’s American bazooka and German Panzerfaust, 9mm and handheld antiaircraft launchers during WWII, the now infamous RPG’s and disposable LAW’s, the current and venerable 2.75“, MLRS and SMAW and similar systems.

In my particular twist on rocket weapons there are four more pivotal historical events. First was 1910 Henri Marie Coanda’s realization of what is today called the “Coanda Effect”, then in 1913 comes the Father of modern rocketry, Robert H. Goddard and later his invention of his liquid fueled rocket (a puller design) in 1926 followed by his lifetime of research, third was Robert Mainhart, Art Biehl and the others of MB Associates with their ”Gyrojet Rocketter” concept around 1960's time frame, and most recent contribution to my design was the Russian concept of the supercavitating “Schval” torpedo also from the 60‘s.

Oh, Yes, let's not forget that Newton fellow and something about "equal but opposite reactions", he was in there somewhere…..

Photo of Robert H. Goddard’s first liquid fueled 
rocket at Auburn, Massachusetts, March 16,1926

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