22 January 2017

FWS Armory: ROCKET GUNS by Yoel

The 60's were a great time to be alive, the Space Age was carried us to the stars on the wings of the Saturn 5 rockets and the label of “rocket scientist” was the highest title for one’s genius. Here on Terra, the rockery entered all branches of military organizations worldwide: the air-to-air missiles grounded the aerial machine guns, surface naval missiles sunk and retried the battleships with their massive cannons and even ground cannon artillery had to start sharing its habitat with artillery rockets and missiles. One field of death and destruction that seemed to be spared from this rocket craze – the small arms. Those good old sluggers stayed unchanged from the early days of the hand-held cannons predecessors with modern firearms  adding durable materials, longer ranges and higher ROF…but in essence not so different. In the mid 60's one small weapon firm contended for beating the bullets in their own home field, the MBA Company of San Ramon, developed and (tried to) sell rocket pistols and carbines to the masses called “the Gyrojets”. MBA's bold experiment mark the high point of attempting to streamline rockets into cutting edge small arms' armament. Others tried before and after, but ‘till this day, the Gyrojet remained a non-fulfilled promise of fusing rockery and military small arms. This article will address those forgotten children of firearm history and give them the respect they deserve.  

This article, and particularly its history segment, could not have been made possible without the joint effort of these contributors and advisers worldwide:

-Shigeo Sugawa, expert on Japanese guns history and author of many books on the subject.

-Anders Norgreen Olsen of National Museum of Denmark and Kock Ditte of Historiecenter Dybbøl Banke.

-The main source of information regarding MBA history armament and rockets is from Mel Carpenter excellent book: An Introduction to MBA Gyrojets and Other Ordnance.

This article focuses on small caliber rocket launchers firing largely unguided rockets without any kind of explosive payload, which achieves lethality similar to regular bullets do – by kinetic energy. Those launchers explored are usually be configured as common small arms formats as pistols and carbines. For further reading about more conventional bigger rocket launchers check out an older FWS article

Clarification of Terms
First thing first! It is important to sort through the different names and terminologies associated with small rockets and the other small arms ammunition out there that are often confused and confusing. Those mistakes and general confusion can be forgiven, but need to be addressed and sorted out.

Bullet vs. Rocket
First, there needs to be clarification made between the all too familiar terms: “bullet” and the “rocket”.
A bullet is an externally propelled projectile, launched by high pressure explosion of the propellant. The explosive done inside the firing chamber of the firearm and the pressure buildup is similar to a pressure cooker and accelerates the bullet, like the cooker's lid, down the barrel. The bullet diameter is slightly bigger than the barrel inner-diameter in order to seal the pressure from leaking around the bullet perimeter. With rifled barrel, the bullet locks-in and engages with the rifling is forced to spin for gaining angular momentum.
In contrast, a rocket is a self-propelled pressure cooker. The propellant inside the rocket is burned and exhausted out of the rear side to accelerate the rocket to the target. A barrel, if it exists, is simply used as a guiding tube, providing the rocket a short acceleration path where the rocket can achieve sufficient muzzle velocity before emerging to the outside world where gravity and side winds may divert its course. Rocket guns' barrels inner-diameter are slightly bigger than the rockets and they are always smooth-bore. If the rockets need to spin, the rocket must achieve it by its own.

Rocket vs. Caseless Bullets
A common muddling that exists is between rockets and caseless ammunition. The reason is that both types of ammo launch a projectile out of the barrel without an spent case needing to be extract manually or eject automatically out of the gun's other end. While similar in that feature, the causes are different for the Rocket and the caseless bullet. Caseless ammo, as implied by name, is literally an “no case" bullet that does not have a casing of any type to eject. The propellant is a solid block that cocoons around the bullet and is burned off once the gun is fired. In the case of rockets, the casing and the projectile are not different parts, the rocket is a hollow bullet filled with propellant. When ignited, this self-propelled case leaving the barrel without any case left behind.

Rocket vs. Rocket Ball  
More subtle clarification is needed when discussing the difference between the rocket and a type of ammo usually dubbed “Rocket-ball”. In the 19th century, when humanity started tinkering with the early metallic cartridges, the question of how to remove spent cases after firing became quite an issue. The Rocket-ball was hollow backed bullets contain gunpowder and sealed by a cover. The Rocket-ball operated similar to the rocket, self-propelled projectile expelling burned propellant from the rear side. The difference is in the burning rates. While the rocket's propellant burn rate was relatively slow and the rocket continue to eject rear jet after leaving the barrel, the Rocket-ball burns out completely when the bullet leaves. Rocket-ball had minor advantages over regular cartridges in not having spent cases to be extracted and ejected, allowing the gun mechanics to be simpler with higher ROF. The disadvantages, to name a few, are relatively weak and slower bullets compare to similar size cartridges and might be easily corrupted by the environmental elements compare to the protection of the full metal cases.

Stabling methods
Dumbing down external ballistic for the purpose of this article, the main concern achieving the goal of delivering the round onto the target is to keep the bullet trajectory as close to an straight line as possible. As air drags, it dissipating bullet velocity along with energy, so aerodynamics bullets tend to be pointy-nose shaped. The problem with such silhouette is that the center of air resistance is located before the center of mass and the result is a positive feed loop. Similar to a level pencil on its point, having center of air pressure before the center of mass conditions small angled deflection to increase. Both bullets and rockets with those deflections from original direction will result in projectile missed its target. Several methods were implementing to ensure steady and straight journey:              

Placing the center of mass before the center of air resistance could be simply achieved by adding a long pole or stick behind the main mass of the projectile.  

Fined (fixed + foldable)
An extension of previous methods is to have fins in either fix or foldable mounted at the rear of the projectile, further push the center of air resistance backward. These are one of the most iconic features of any rocket-based system. 

By gaining spinning before leaving the gun or launcher a projectile adds angular momentum in the direction of flight, thus make it more resistance to any orientation deviation from original course. Almost all small arms nowadays achieve such angular momentum using rifled barrels.

History of the Rocket Gun
The rocket originated in the 13th century at the birthplace of the gunpowder – ancient China.  The early rockets were bamboo sticks filled with gunpowder and attached by long thin poles used both for sticking the rockets in the ground before launching and adding stability by moving the center of air drag behind the rocket itself and the mass center. The Chinese used these primitive rockets as a siege weapon and as incendiary missiles. Those early rockets were used by the Chinese to fight against the Mongol invasion and one another. It wouldn't take long before the Mongols found out the secret of gunpowder and rocketry, adapting the rockets into their own arsenals. From there, the rockets usage spread across the world via the extensive Mongol empire. First among the south-east nations of Asia: the Japanese and Koreans and later through the conflicts between the Mongol empire and on to the Muslim then onward to Europe as well. The origin of the word “rocket” came from Italian word rocchetto meaning bobbin or a spool referring to the rocket cylindrical shape. Rockets were used primarily as artillery weapon by the powers of Europe and Asia, but they were crude, less accurate than the ever-evolving cannons. There are some notable rockets guns from history:

The Japanese Tanegashima Rockets
The first recorded marriage between guns and rockets happened in 15th century Japan. The Japanese already had their own version of Chinese rockets called Bō-hiya (棒火矢) used for incendiary purposes. In the 15th century a new technology appeared in the islands, the first European matchlock guns brought by Portuguese adventurers that had to anchor due to a storm at the Tanegashima Island. The Japanese bought two of those matchlocks and through reverse engineering produce their own matchlock named after the island, the Tanegashima matchlock. Combining old and new, the Tanegashima were used, other than just being a simple matchlock gun, as a mounting platform for the Bō-hiya rockets as well.
Not so different from the modern use of muzzle fired grenades, the Tanegashima could be used to launch indirect fire as well as line of sight. Firing the rocket, the Japanese gunner, either Samurai or their foot soldiers (the Ashigaru), did not need to fill the barrel with gunpowder but simply insert the rocket pole in, the Tanegashima, had been used as a mounting for aiming the rocket. The rocket inflammable cord would stick out from the part of the rocket outside of the barrel and the gunner used his already available ignition tools to ignite the cord. Besides land engagements, the Tanegashima found their way onto the high seas in the hands of Japanese naval vessels as well as pirates. Battles were wages with both sides firing a number of these rockets. These were likely phased out after the end of the Tonkagawa Shotgune period and the information on the Tanegashima remains limited in other languages besides Japanese. An example of an Bō-hiya along with some information can been seen at Matsumoto Castle in Nagano Prefecture.

The Danish Voss Musket Rocket
The next great leap in Rocket Gun history was the Danish Voss rocket. Loaded as an ordinary musket ball with black-powder, the Voss rockets were launch out of the musket as an all too familiar slug. The blast also used to ignite the rocket engine a split second after clearing the smooth-bore barrel. The rocket wasn't fined stabilized, like the Bō-hiya centuries older, but it didn't have to be. The initial trust of the black-powder shortened the time-to-target, allowing it to deliver a small payload of incendiary substance. 
The Voss rocket served the Danish army for the two Danish-Prussian wars of 1848 and 1864, but was out of service in 1868 when Denmark signed Saint Petersburg Declaration which prohibit explosive and incendiary bullets under 400 grams in mass. Although the Voss wasn't intended for anti-personnel use it falls under the declaration criteria. One side note on my behalf, the Historiecenter Dybbøl Banke (Dybbøl battle history center) where half of my info regarding the Voss rocket came from was built near the ruin of old farm burned down by the Danish army at the battle of Dybbøl using Voss rockets. 

The Clyde Farrell SMG 
Some 30 years before the Gyrojet, an American inventor name Clyde Farrell of San Francisco was featured by Modern Mechanix magazine in their July 1934 issue as the inventor of an “Rocket Machine Gun”. This gun was a belt fed gun, and claimed to firing at 700 RPM with no recoil or overheating and weighting at just 3lbs. There were no mechanical details presented about this gun in the article to substantiate those achievements or claims. The article states that Cylde Farrell's rocket bullet firing Sub machine gun is being tested in Washington DC. There are no other reports about the gun or the inventor and no patents register for rocket guns or under the name of Clyde Farrell. Sound like another case of combining an overconfident inventor and credulous reporter. Searching for Clyde Farrell today has the few internet entries claiming that the rocket bullet firing SMG was an hoax.    

The 9mm German rocket 
Sandwiched between the rocket ball and the rocket was the daring experiment of the 9mm rocket bullet program Nazi Germany conducted during the Second World War. The German S-Munition was the brain child of Dr. Heinrich Langweiler, a noted physicist famous for his invention of the hollow charge of the Panzerfaust, and the S-Munition was  an attempt to test and utilized Langweiler's “Impuls Antrieb” (pulse drive) theory. 
The theory was  based on the idea of creating an constant pressure wave following the rear end of the projectile to produce higher muzzle velocity with lower pressure-time curves leading to lighter and cheaper barrel and gun. Partly the theory was implementing in the V3 super-cannon with its multiple explosive chambers along the barrel. For small arms manifestation, the tested bullets were hollowed shells filled with gunpowder burning and exhausting from the rear nuzzles as it accelerate the bullet to the muzzle. The rockets were 9mm in diameter with different lengths tested and were constructed out of stainless steel. Rockets were designed to be fired from smooth-bore barrel and produce low and constant pressure in the gun contrast to regular cartridge propellant burnout producing sharp high pressure peak in the first millisecond and subjecting the barrel and bolt face to extreme mechanical stress.Reducing the pressure could result in lighter and cheaper guns, replacing the brass cases with stainless steel which were more available and having potent ammo while firing it from simple and cheap blowback operation gun. 
All those arguments appealing to the Nazi German war machine in the latter years of the war when it was stressed by lack of resources and Allied bombed factories. The rockets were stabilized by the “javelin” as the exhaust nuzzles weren’t angled and the barrel was smoothbore. However those promises weren’t fulfill, testing result by both the Germans themselves and allied nations' attempts to reverse engineer Nazi technologies after the war showed poor velocities and accuracy results. As for the guns intended to fire those rockets? British intelligent agents instigate Dr. Langweiler after the war and gather intel about the experimental technology speculate a smoothbore "Schmeisser" (MP-40) though no such sub machinegun ever found. They speculate that the rockets were contain inside more or less regular pistol cases with small amount of gunpowder, an hypothesis seem valid given the French's S-Munition reverse-engineering documents describe such munition. The purpose of this design is three fold: the small charge in the case ignites the rocket engine; the slightly bigger diameter of the case fixed the cartridge in the firing chamber waiting to the striker punch and lastly provide method of removing dud rocket out of the barrel by cycling manually.          

The Fliegerfaust
As Allied forces flanking Nazi Germany from all directions, the air superiority that the Luftwaffe enjoyed in its heydays faded fast and German ground troops could no longer relays on their air force to block incoming enemy close air support planes. The Wehrmacht needed a solution, a weapon mobile and flexible enough to be carried by foot soldier to take down low-altitude planes. The result was the "Fliegerfaust" (plane fist), also known as the "Luftfaust" (air-fist), a shoulder launched spin stabilized, electrically ignited 20mm rockets with small explosive head. The first experimental model, the Fliegerfaust A, contained four barrels and never went to full production.
The second, Fliegerfaust B, contained 9 barrels and have a range of 1500 feet. The two models designed and produced by the HASAG factory at Leipzig in 1944 using forced labor. Out of the 10,000 ordered by the Wehrmacht, only handfuls were delivered. Little is known about the Fliegerfaust B, it is believed that this bundle of barrels fired 4 rocket salvo followed by the other five left with 0.1 second intervals between each shot to prevent each rocket exhaust fumes of one rocket interfere with the followed rocket.
The launcher was reloaded from the rear by attaching a 9 rounds clip-disk. These disc-clips were carried in a cylinder-shaped canvas shoulder bag that carried only one reload per bag. It is unknown how effective the Fliegerfaust B was against Allied CAS aircraft. And I know what you are thinking, could this be used against tanks, infantry, and building? This is just another example of how advanced the thinking was by the Germans and how they would try radical concepts to counter an issue. I wonder if this weapon will wind up an a future World War II video game shooter?  

The history of MBA
MBA or MBAssociates was a company founded at April 1st, 1960 (no, it's not an April fool trick!) by two friends and workplace associative Robert Mainhardt and Art Biehl, Hench the M and B in MBA, as a high tech cutting edge R&D company whose main clients are government branches like the military, law enforcement agencies, NASA, and more both domestically and abroad. One of MBA's first projects was funded by an DOD research grant for developing rockets as small as darts with the clear purpose to be used as anti-personal rocketed flechette for the raging Vietnam War. Mainhardt & Biehl accept the challenge (and money) and developed the Finjet. 
Both Mainhardt & Biehl seemed fallen in love with the idea of small bullet size rockets that the two dedicated a large fraction of MBA's money, time, and manpower into the development of micro-rockets and their launchers even after it should be crystal clear that no government was interested in their rocketeer revolution. As government contracts never materialized, MBA headed to the civilian market with MBA's flag product, offering the Gyrojet launchers and rockets for sale to the American public. As many as 1000 Gyro launchers and 1 million rocket ammunition were manufactured. Costumers' reaction and evaluation weren't favorably toward the Gyrojet and MBA sales were weak to none. There were quality control issues with rocket ammunition failing to ignite and more alarming, a hangout rounds due to low quality control and manual assembly of the rockets. MBA continued to promote the micro-rockets concept until to 1980 when the company was sold. MBA's buyer, Tracor Inc., bought it mainly for the aerial countermeasure systems patents and knowhow. Tracor Inc. dumped the failing Gyrojets and other MBA rockets to the bin of history and into gun & ammo collectors' displays. 

 An Ohioan inventor name Jeffrey Widder tried to dip his toe into the complex world of less- than-lethal-weapons with his 2016 invention: the “Pogojet”. An portmanteau of “Pogo” as pogo-stick and “jet” as in Gyrojet. The Pogojet is a small rocket with telescopic piston hidden inside. When ignited either by electric current or striking pin the burning propellant firstly extends the piston backward pushing the rocket out of the gun with initial speed. The movement of the piston also reveals the channels directing the propellant to the angled nuzzles which further accelerate the rocket and spin it for better stability. 
Such an elaborate design for one purpose - to achieve constant low velocity for extended length of the flight. Low velocity is needed for deliver painful punch without penetrate target's skin.The gun, resembles a short barrel futuristic pistol, could be fired as stand along handgun or slung under other gun. The gun appeared last year in 2015 followed a patent register under Jeffrey Widder. There is currently no indication if Mr. Widder has managed to find some investors for his idea or not, but the invention received some press at the time. 

The Gyrojet Weapon System
The Gyrojet family of products included various rockets and launchers ranging from 2.8mm up to 55mm as MBA experimenting with anything and everything from volley guns to cloud seeding rockets. The commercial line of rockets and launchers were in the 12mm & 13mm diameter and configured in 3 pistol and 2 carbine layouts. 
Other than the barrel lengths stocks and such, those Gyrojet launchers were mechanically and operationally identical.All launchers had 6 rounds fixed box magazine in the pistol grip with hinged swiveling door (in the Model A) and sliding 'breech' (in the Model B) serves as opening for reloading and removing of dud rounds. The hummer is placed in front of magazine and when fired it rise and heat the rocket nose and push it backward against a fixed firing pin behind the top most rocket. 
As the rocket ignites it moving forward and re-cock the hummer forward for the next shot as the rocket continue along the barrel. The momentary match between the rocket and the hummer steals about one tenth of the rocket energy but in return allows the Gyrojet to gain enough spinning and stability before leaving the hummer and the gun.The launchers' barrels were thin aluminum tubes, as the Gyrojet rockets gain their angular momentum from the tilted jet nuzzles they don't need any rifling whatsoever, but being the pistol configurations having smoothbore barrels would classify those handguns as smoothbore pistols or Title 2 “Any Other Weapons" (AOW) under US gun laws. 
In order to exempt the handguns shallow non-functioning rifling added which serve no purpose other than legal one. The safety switch is less than optimal design as it doesn't lock the hummer or trigger but only rise or remove small stopper in front of the fix firing pin resulting in possible scenario where the trigger been pulled and hummer released to push the rocket against that stopper. At best, the shooter might figure it when he tries to switch the safety to find it stack cause of the rocket pressured against it and cock the hummer manually using the lever on the left side. At worst the releasing the safety switch will results in unintended firing. Magazine design was an nonstarter as well, the magazine was fixed inside the pistol grip and contained only six rockets which even in the 60's was disappointing. 
Although MBA tinkering with both detachable magazines and stripper clips loading the Gyrojet launchers done the old fashion way, one by one. Making thing worst the magazine didn't have any feed lips, when open the breech for reloading or removing troubling rocket shooter must press the remaining rockets with one of his fingers to keep them spewing out by the magazine spring. All that made reloading and misfiring handling under fire practically impossible. Initially, the commercial launchers were designated to 13mm diameter rockets. After the 1968 Gun Control Act, MBA found itself with rockets above half an inch, and there for illegal. MBA change the Gyrojets diameter as well as the barrels' diameter and offered its clients to recall their guns for retrofit them to bring Gryojets up being legal. 
All of the commercial models were “semi-automatic only” setting, the hammer re-cocked by the shooting rocket on its way out. However, since the first Gyrojet pistols MBA sent for evaluation to the different branches of the US military, the Model 137, were “selected fire” guns with fire mode selectors on the left side of the gun above the trigger. After the US military direction failed, MBA market the guns to the civilian market, and the fire mode selector was plugged, fixing them on semi-auto only. A bit misconception exists on that matter since some retrofit 137's and brand new civilian models were packed in cardboard boxes labeled as "AUTOMATIC ROCKET PISTOL". Those boxes in fact were left over from the intended military contract MBA expected, since MBA were always stripped on cash from day one any saving method was used, including shipping perfectly legal semis titled as automatic!  

Other MBA products

The Gyrojet Flares 
Gyrojets as a weapon technology were doomed as a total failure, however, few know that the Gyro concept found new home. Instead of killing enemy combatants the Gyrojets can save the lives of pilots and aircrews downed at enemy territory. A Personnel Distress Kit consist of plastic molded bandoleer holding seven red signals tethered to firing pen issued as part of survival vest of air force and army pilots and aircrew personals, those red signals are in fact 0.5 inch Gyrojet rockets containing small pyrotechnic payload for illumination.
The Gyrojet advantages shined in the role of distress signal as the launcher pen is both light and recoilless and the firing is quiet which always a good thing when stranded behind enemy line. The rocket motor is strong enough to break through jungle canopy and continue traveling before igniting the payload.The Gyrojets flares designed by MBA during and for the Vietnam War and labeled as “Foliage Penetrating Signal Kit” as jungle roofing is what downed pilot or aircrew personnel should expect at 'Nam. For this reason the Navy didn’t adapt the Gyrojet flares to its standard issue survival vests. The flares were the only miniature-rockets commercial success MBA had for the entirety of its existence. The flares were also the only mass produced items MBA ever sold as the other rockets were at least manually assembled. MBA continue selling the flared till they went under when Tracor Inc. bought it in 1980. Tracor continue producing those rockets afterward.

The Finjet & Launchjet
While Gyrojets rockets and launchers are what MBA is most famous for, but at first MBA  Microjets weren't spin stabilized. The first attempts to developed and market a miniature rocket MBA aimed at self-propelled flechett called Finjets. Those darts size rockets were intended to all sort of applications ranging from salvo firing handheld launchers for South-Vietnamese rice farmers to aircraft belly payload for sprawling thousands of arrows against ground forces. Though there are many configurations and usages been speculated and proposed to different branches of US military none was answered by a contract. As MBA continually experiment with Finjets firing and flying tests, they noticed that some finless Finjets (if a Finjet have no fins does it a Finjet?) used as control group demonstrated better than expected stability, the added heavy reinforced nose tip added to Finjet's head for better penetration improved its stability too. A finless rocket has many advantages over its fined kin: 
-having fins creates drag force reducing rocket terminal velocity and increase velocity drop rate once the rocket engine run dry.
-Fins reduce the rocket penetration ability to the target as those pesky fins blocked leaving only the pointy head inside.
-Packing density at storage and inside the weapon decreased as the fins prevent close parallel pack side by side.                 
-Mass produced of tiny hollowed darts is more complex and expensive than bare cylinders closed from one spiky end. 
As a result of failing to find a customer to their Finjets, MBA tried to market finless rockets, called Launchjets, for that niche where over-saturated a target with cheap penetrating rockets is more important than accuracy – landmine field clearance.The proposed design include a rocket propelled salvo-launch box fired from armored vehicle above minefield where in midair it will spray the land with thousands of Launchjets, each carries small dose of incendiary component to trigger mine explosion. The Launchjet extreme length to diameter ratio provides it with sufficient penetrability to deliver its explosive several fit under to the mine. Firing tests showed good results but it was for no good… the US Army wasn't pull its wallet. Last attempt to find market to the Lanchjet was for the field of underwater firearms, several models proposed and built with the hope to draw the navy to the barging to arm its divers but again, with no luck what so ever.

The Gryojet in Vietnam
The Gyrojet was never accepted to regular service in any United States military branch although several pistols were bought personally by officers and brought with them to ‘Nam. The only unit ever equipped with Gyros was the legendary US Military Assistance Command Vietnam, Studies and Observations Group (MACV-SOG). The unit conducted covert guerilla warfare operation in Vietnam (North and South), Laos and Cambodia. As only one of many experimental guns and technologies used by MAC-V-SOG was the Gyrojet pistols issues for their silence operation and superb pentation. There is no official record that any Gyrojet, SOG or other, been used in a battel let along any recorded Gyrojet enemy kill.

Advantages of Rocket Guns

Light Weight
The rocket launchers don't have sustain the high pressure and blazing temperatures that their guns counterparts have and this allows rocket launchers to be made from thinner and lighter materials, thus,  making them much lighter than similar sized slugs throwers. For example, the Gyrojet pistol weight is 0.4Kg (.8 of an pound) while the comparable Colt 1911 weight in at 1.1Kg (2.43 lbs).

Almost no Recoil
Recoil is a natural effect of slug thrower and since nearly the beginning of firearms, there have been many attempts to overcome recoil.  Rocket guns could be one solution to the issue of recoil since there is no high pressure built inside the launcher tube-barrel, the release of the projectile from the muzzle doesn't generate the recoil kick that gun wielder needs to handles. One of the photos taken of Robert Mainhardt with his Gyrojet Carbine, Mr. Mainhardt level the carbine stock against his nose tip as he fire counties rounds to prove the Gyrojet lack of recoil, as he put his nose integrity on the line, that what I call standing behind your product!  

Terminal Energy 
Bullets leave the barrel at maximum velocity and quickly lose their speed while rockets leave at slow pace and gain velocity as they reach maximum kinetic energy and velocity far from the muzzle. The cleaner, more efficient burning of the rocket fuel result in a higher maximum velocity than bullets. Coupled with the fact that usually the enemies are engaged behind point blank ranges lead to bigger punch at combating ranges. In the case of the Gyrojet rocket it been calculated the rocket deliver 50% more kinetic energy than .45 ACP round.  

Price of Launchers
There is always several prices associated with any weapon systems. Two of the largest are the cost of the weapon and the ammunition. In the case of rocket guns, the launchers can be made from lighter cheaper materials and don't have to contain a high pressure mean that you don't to fabricate parts with high manufacturing tolerance. The firing mechanism is also simpler with far fewer parts all pushes the production cost of the launchers down.

Thermal Build-up & Foliage
Guns and rocket guns are essentially converting machines, converting the chemical energy of the propellant to projectile kinetic energy and as the Second Law of Thermodynamics dictates that no conversion is 100% efficient. The propellant burning produce heat and residues, when that burning occurs inside a gun it heat and contaminate the gun. Rockets however most of their burning phase is outside of the barrel.

High Firing Rates
With minimal thermal build-up and foliage , no need to extract and eject empty cases and no high pressures in the barrel preventing round chambering and fire before the previous round left the barrel rocket guns could have amazing rate-of-fire limited only by the rate of loading new rockets to the barrel.

Low Acceleration
Rockets leave the gun at low speed and slowly accelerate to top velocity. Such a low acceleration makes development of more complex slugs than possible with conventional bullets. The task of miniaturization of explosives, fuses, sensors, guiding fins etc. is much easier when not have to deal with the mighty G force bullets endure.

Minimal Back Space
The Gyrojet layout of hammer located in front of the magazine and pushes the Gyrojet rocket against a fix firing pin is clear indicator to what such arrangement re-configured into a bullpup carbine, a bullpup rocket gun will have the most barrel to gun lengths ratio theoretically possible with magazine housed literally at the rear end of the gun with only fix firing pin separates the magazine rear end and the shooter.  

Minimal Side Space
Not having to eject empty cases enables to cluster several barrels side to side and/or above-under without the same penalties as a conventional slugthrower .

Fewer Moving Parts
Rocket guns are practically a simple tube with feeding system and trigger unit. No bolt and carrier, extractor, ejector, charging handle or locking system like conventional firearm. Fewer moving parts guns allow for the rocket guns to be more reliable and less prone to jamming along with their field strip being easier and quicker than normal firearms.  

With no high pressure in the barrel, the rocket emerging from the muzzle won't generate load muzzle blast and while such rocket can produce supersonic crack if they surpass the sound barrier like bullets do, however such supersonic crack will occur far from the shooter and won't reveal his position. This one of the reasons that the US Army MAC-V-SOG unit in Vietnam explored the possibility of using MBA Gryojet weaponry and could mean that sound suppressors would not be needed for Gryojet weapons.  

Disadvantages of Rocket Guns

Short Range Handicap
Rocket guns Achilles' heel is their pathetic punch at short ranges as the rocket initial velocity is very low until it gains full speed only after few meters of flight. Any target closer than that distance will be hit by weaker blow than a normal bullet. At point blank range, the rocket is useless, some sources claim that the one could block Gyrojet rocket from leaving the barrel with a bare finger with no harm! The rocket engine was far too weak to push the finger, and the rocket would simply dissipate its fuel supply dry inside the barrel.

One of the commonly reported issues with Gyroget weaponry is that rockets themselves suffer from accuracy problems linked to several issues. In the case of the MBA Gyrojet weapons is that their own rocket ammunition was of such low quality with between 1%-10% of the ammunition misfiring or being a complete dud. These issues with misfiring caused the finless unguided rocket, which are not accurate anyways, to have the vent ports used for stability to fail or misfire…dooming the rocket bullet to spin-off target like some black powder smoothbore round. Another reason was that the rocket’s initial velocity is low and any small side wind will easily push it off-course from the target. Coupled that with the previous disadvantage of minimal killing range limit the Gyrojet can and was summarized by some 60's government official as: "If the target is close enough to hit, you can’t kill it. If you can kill it, you can’t hit it"

Price of Rockets
In my country, Israel, there is a grim joke about motorcycling and directed to motorists: "what time you may save in the traffic jams you will repay in the Intensive Therapy Unit" and with that cheerful attitude in mind we'll address the rockets price issue. Current price of Gyrojet rockets is staggering at $100 a pop, but even back in the jolly 60's, MBA couldn't push their price below one dollar (remember it was an 1960's dollar!). The reason is simple, machining and fabricating rockets require precise work, the thrust nozzle should be evenly drilled in the right angle or the torsion spring in the retractable fins should have the correct spring tension and so on. Every attempt to mass produce such delicate small slugs will be a major challenge. On the contrast cartridges are relatively simple to mass produce cheaply. In summary regular guns construction is expensive while the cartridges are dirt cheap and rockets guns are vice versa. Whatever price reduction you gain with the launcher you will repay with the rockets…    

No Way the Actuate Feed System
Modern small arms are relaying on auto-loading for providing continuous fire without manual cycling. With the exception of miniguns and chainguns, all autoloaders actuate by taping to the high pressure generate by the propellant burn to cycle the bolt. Since rocket guns don't contain high pressure there is no means to actuate the gun. Although rockets gun don't need to chamber new round and eject spent one they do need something to push new rocket to be align with the barrel and firing fin. When the gun is magazine-fed, everything is Okie-Dokie but not so much if you want a belt fed rocket LMG.

Double Stacking Feeding Problem
As stated above, a magazine-fed rocketeer the magazine's spring pushing rocket to face the barrel and firing fin without any bolt picking and chambering, the rocket simply shot out of the magazine into the barrel. When the magazine is non- staggered double stacked there is the problem of having two potential firing potions with only one barrel and one firing fin to fire with.

Barrel Lag
Though very short event the time takes the rocket from ignition to leaving the barrel is still a consideration. Any shaky hands or poor training will results in barrel turning out of target before the rocket escape out causing to miss the target.


Anti-armor duties 
Battlefield of decades to come maybe be different than today with the possible advent of the development of ballistic body armor for the protection against shards and shrapnel. The ballistic armor of today can protect from pistol rounds and in near future maybe against assault rifle fire as well. In the further future, powered armor and armed unmanned drone could be added to the list of bullet resistant foes. Many of the SF solutions like Gaussguns and Lasers are far beyond our current level of technology for small arms usage and likely won't be cheaply available in man-portable variants at time to face those threats.Enter the rocket gun! Both deliver more punch above its weigh classt and could fire continuous fire of heavier rockets than the sluggers can without kick its operator due to recoil.    

Space (Freefall & Ground)
The potential use of Gyrojets in space was massively endorsed by MBA's PR machine back then during the heady days of the Space Race/Cold War and even till this day, this usage surface around in any gun enthusiast internet forum when the highest frontier will be finally militarized. More often than not the Gyrojet recoilless perk is claimed to be the reason to arm the space marines with those guns. While the recoil is something that should be consider when fighting in freefall and on the surface of planets and moons with low gravity there also much serious reasons to prefer rocket guns up there.
First and foremost is the concern of thermal build-up, in the hard vacuum of space there is no cooling by natural convection only feeble radiation. Regular gun will be heated very much very quickly and won't be cooled down fast enough. Second is this nutsy vacuum welding phenomenon, when two or more metallic parts are move one against the other they continuously removing the protective oxide surfaces. On Earth, the oxygen in the air endlessly replenishes those protective layers.With the obscene of oxygen metallic parts from similar metals in contact to one another will be welded together. A problem in common slug thrower that can be easily avoided in rocket guns as those could be construct of a wider range of materials. And last but not least, with less foliage and simpler structure, a rocket gun is easier to field striped & cleaned and have less jams to operate which is great when you need to do it with gloved hands of the spacesuit.              

Water isn't friendly environment for traveling bullets to pass through. The high water drag is proportional to the square of the speed, bullets leave the barrel and enter the water at a high velocity results in high drag and sharp decline in bullet speed and kinetic energy. Rockets, however, can build up a speed as the rocket engine accelerates them to moderate but still effective velocity.      

Crime & terror
A rocket guns proliferation could undermine our civilized world to a degree that most don't imagine or understand. Mass production of unregistered illegal guns could be done by the most simplistic machining and labor unlike regular guns fabrication required high level metallurgy and machining. Rockets are fired without inherent any striations or markings of the barrel and their no case to place under microscope making forensic examination useless.
Rocket guns are quieter than any suppressed gun and will leave little gunpowder residue on the shooter's hands. They could be made of variety of materials to pass metal detector and X-ray exams, John McClane may finally get his German made all-porcelain Glock 7! I think I found a possible answer to fermi paradox – we don't see alien civilizations around because sooner or later they all develop rocketguns and go extinct…One of the criticisms against the Gyrojet it was feel like a cheap toy to handle, compare to the all steal guns the Gyrojet was big but remarkable light. An unsuspected security guard could hand-wave a deadly weapon as toy and pass it along.      

Child soldiers
A much grimmer outcome if rocket guns succeed is they could become the weapon of choice to any petty 3rd World warlord to arm any toddler he could draft or steal into his ranks.At an oldie Poplar Science article about arming US allies, South Vietnamese and Laosians, the article address the problem of arming "our little allies". Giving that average Asian is smaller than typical American one of the answers was to arm them with cheap, light and recoilless rocket guns. This is one of the reasons that the old World War II/Korean War M1 Carbine was issued to ARVN troops. Such arguments will play well for children also. Light and recoilless, the rocket gun fits the child's small frame. It is simpler to operate, maintain and clean and require shorter training.

Corner shot
With no recoil, rocket guns will perfectly suited for the job of corner shooting. Equipped with special cameras that transfer sights to shooter’s head display, they could pop around corners to scoot-and-shoot while the shooter is safety hidden and the aiming picture in their personal HUD would remind true due to the simple lack of recoil.    

Realistic Configurations

Closed Loop Sealed Disposable Magazine
One aspect of rocket guns to keep in mind that there is no firing chamber or chambering processes required, rockets ignites while in the magazine and can literally launch out of the magazine feed lips. MBA experiment with Micro rockets showed how sensitive rocket's nozzles are to small dirt, sand or debris which real life guns are all too familiar with. A possible solution could be a closed loop magazine. Imaging a gun magazine where the two feed lips been extended further to form a closed sealing above the rockets with two circular holes, in the rear-top side and front-top side, basically the magazine is a weaponized Pez dispenser! Those holes be covered by a thin foil protect the magazine contents from the elements (similar to the H&K G11 caseless ammunition). The magazines will be delivered to the troops preloaded and sealed as disposal magazines. As with the Gyrojet the front hammer will move backward tear the front foil and push the top most rocket through the rear foil to meet the fix firing pin. Such arrangement could provide the magazine and its rocket needed protection from unforgiving field conditions while enabling quick gun reloading.   

Double Stack Arrangement
The problem described above in the disadvantages list of need to have either single column magazine or staggered one could be avoided by having rocketeer that can shot its rockets from both of their alternative possible positions. Such a launcher will have wider hammer that can push back rocket be it waiting in left or right against two parallel firing pins to ignite the rocket. The rockets then shot out of barrel with cross-section of two partially overlapping similar diameter circles (called in Latin Vesica piscis). This barrel can accommodate rockets fired from both possible positions.     

Foldable/Detachable Barrel
The rocket gun barrel is nothing more than a smooth bore thin wall tube, that does not have to contain high pressure and the absents of rifling it is possible to design the rocket gun with removable and/or foldable barrel. True, even regular guns can have detachable barrel but those have a barrel removed as a solid unit that couldn’t be break into parts. The barrel of a rocket gun can be separate to several tubes and assembled again.  

Fast Hammer Cocking
Unlike sluggers that need considerable force to rack the bolt backward before first shot rocket gun's hummer could be mechanically designed to be cocked by the insertion of fresh magazine into the gun, speeding the time needed for first shot.  

Last Rocket "Bolt Stop”
Modern gun usually have bolt stop to lock the bolt at backward position after last round have shot. The bolt stop hold the bolt for magazine reload and similar mechanism can be added into the rocketeer to lock the hummer when magazine is empty to prevent the shooter from releasing the hummer in vain.     

/Shoulder/Helmet Mounted Launcher
Small arms configurations generally boiled down to two layouts: handgun and stocked gun. Both layouts are dictated by the necessity to counter the gun's recoil by transfer it to the shooter's body. The lack of recoil rocket guns enjoys and their light weight mean that other designs are possible. Launcher can be mount on wrists or place on top of shoulder with automatic targeting system like seen in the movie Predator, they can also mounted on steady cam arm as seen in ALIENS with the M56 Smart Gun LMG.         

Secondary Under/Upper Slung Gun
For providing average GI Joe a punch above his weight class would be an secondary barrel and magazine incorporated to the standard rifle. Different rockets packed in several different magazine could allow the launcher and the shooter the flexibility of armor piercing against light armored vehicles or rocket propelled grenades against troops and such.        

Underslung Shotgun for Rocket Carbine
A potential solution to the short range blind spot rocket gun have is attaching short barrel shotgun under as a secondary gun. The most efficient rocket gun layout will be a bullpup carbine, enjoying the barrel light weight, the lack of spent cases to eject and the lack of bolt's reciprocate space the gun will stretch the layout into extreme with magazine housing less than an inch from the gun edge. A shotgun, pump action or self-loading, underslung under the rocket barrel will supply the lethal dose for any encounters of the close and personal type. Oddly, this future rocket gun will be very similar in layout to the Mobile Infantry's Morita gun meaning Paul Verhoeven will likely have the last laugh! 

Micro-rockets may have surprising applications if future manufactures could push their cost low enough. Rockets guns don't have recoil, thermal build-up, foliage and empty cases to spew. If the rockets can be made cheaply enough the troops of tomorrow could carry machine-rocketeer. Light and recoilless SAW spraying deadly silence rockets at high ROF without any fire flash or vehicle mounted gun, all could benefit from such an angel of death on their side. One road block (other than rockets' cost) be that any belt fed guns will need some electrical motor feeding system to pull the belt out of its pack and into the gun as there is not enough pressure in the gun to actuate feeding cam as regular machineguns do. Any belt fed machine-rocketeer will have to be chaingun too.         

Volley Gun
A cool element rocketeers have is the ability to cluster several barrels together. There are no empty cases to eject and no “wide-shoulders” bolts to house and there little recoil, barrel's weight and thermal build-up. Having multiple barrels further increase the rocketeer already insane ROF. Since rocket guns don't really need to be chamber the rounds but simply place the rockets in line with the tubes an intriguing and weird feeding alignments are possible: Side-by-side barrels. These barrels array could be fed from side by side parallel magazines block similar to the Russian experimental TKB-059. Other layout can be vertical array of barrels, one above the other, firing the first rockets in the magazine out as many as the number of barrels the gun have. Since there is no single bolt that chamber and extract all or recoil it doable to have a selective fire mode, adjust the number of barrels firing for any volley as needed.           

Rocket Shotshell
A foot-in-the-door tactic to introduce rocket guns technology to the American civilian gun market (A multi-billion industry in annual revenue) could base on a loophole in NFA regulation exempting shotguns and their ammo out of the 1968 gun control act as a distractive devices.
The act classify any gun fires a round bigger than half an inch in diameter as a destructive device and therefore banned for the public. The only exception to the law is a shotgun vaguely defined as such as "any [gun] the Attorney General finds is generally recognized as particularly suitable for sporting purposes". 
Since the rockets miniaturization process will be the major difficulty at producing reliable and cheap rockets, as evident by the Gyrojet example, it more than likely the first micro-rockets be on the large side of the caliber spectrum. Any attempt to market larger than 0.5'' rocket guns will be blocked by the 1968 act unless those rockets will designed in shotgun bore sizes and market as shotgun shells for 'sporting purposes'. A future attorney general if he want to be a dick may question the need for high velocity high penetration rocket for sporting given no self-respecting deer would be catch wearing a ballistic body armor but since crazier shotgun shell are already legal today he/she may have to pass it too. There many advantage for shotguns loaded rockets from the technical aspects too. Many civilian shotguns are manually cycled like pump-action and lever-action so the absence of autoloader ability of the rocket gun will be a non-issue. 
Chambering fresh rockets and extracting not-fired one will be done manually as God and role-of-cool intend it to be. Like the old Gyrojet, shotguns' barrel is usually smoothbore so no problem there either. As with regular shotgun shells, different types of rockets could be loaded and fire cause shotguns are omnivores. Last but not least, the chief reason rockets manufacturers may chose the shotshell path is the simple one: the foremost hurdle any futurist and revolutionary weapon system had to surpass when market it to the public is the customer valid concern that if the gun manufacturer will go under the customer will be left with nicely useless gun with no special ammo needed as happened many time before when someone tried marketing a special gun fed with one of a kind cartridges. The shotshell resolve that conundrum as the rocket guns themselves are simple good-Ol' shotguns everyone have and love and the only thing that is sold are the rockets.

Sniper rifle and Anti-material Rifle 
With the quiet, light, no muzzle flash, recoilless and having extra punch at longer ranges of an rocket gun, they could be suitable platform for sniper, marksmen, and anti-material roles.

Is the Bolter the Answer?
Scrolling through the Realistic configurations list any WH40K zealot might ask "where the hell is the Bolter?!" Indeed, the Imperium of Man Boltgun is the most recognized and familiar fictional rocket gun today. The Bolter is a more or less continental gun with likely smoothbore barrel fires the massive Bolts. The Bolt itself is an enlarged cartridge with a Gyrojetic-style rocket with internally exploded warhead as its projectile. The propellant in the cartridge is sufficient enough to launch the rocketed bullet at high velocity out of the muzzle before the rocket engine kicks in and further accelerates it. Could similar scheme be the answer to the short range pathetic lethality problem of the rocket guns? The answer sadly is no. The reliability and accuracy difficulties the Gyrojet faced back then were largely the result of either low quality jets' nozzles machining and alignment or one of the nuzzle been clogged by dirt or such. Installing Gyrojet with its delicate nuzzled back-plate pacing the blast of the propellant isn't likely improved that reliability and accuracy Gyrojet's characteristic. Also, any projectile subject to high G's of the firing will had to be designed as rough as possible meaning the amount of rocket propellant will be minimal to none.

How will it feel to Shoot an Rocket Gun?

Shooting a rocketeer will be a different experience than normal slugger. There are very few who fire Gyrojet and are still alive today, so the information about “how will it feel' will be dictated by the experience of small number of people and some common engineering sense of my behalf. The first thing the shooter will notice when feeling the trigger is… very little. There is no real recoil, no muzzle flash or blast noise. A warm gentle breeze flow through the venting holes carries small odor of gunpowder and noting more. A shooter familiar with regular firearms and familiar with the notorious reliability of the Gyros might conclude it yet another case of dud or hangout rocket. 
If there no close target to indicate a hit the shooter probably won't believe that the rocket was indeed fired. Under dark a shooter could notice however the rocket gun flares as the rockets' engines are glowing for a split of a second after leaving the muzzle. Luckily for the shooter, unlike tracers, other than the shooter, no one can notice those flares since the rocket nuzzles are directed toward the shooter. Sadly for the shooter, unlike tracers, the engine glow faded quicker than tracers making them useless for tracers' duties. Experience shooter is trained at recoil management and the predisposition and muscle memory tends to push the muzzle lower to resist muzzle climb. With no recoil and longer barrel lag of the rocket gun the shooter will notice that he keeps hitting the ground lower to the target at burst or double tap firing. 

Science Fiction and the Rocket Guns
The first appearance of rocket guns in science fiction is in the first Buck Rogers novel: Armageddon 2419. The protagonist, still called Antony Rogers, was a World War One veteran awake in the 25th century to find America been conquered by the Chinese. The Americans are packed in tribes, called gangs, and armed with rocket guns they use to fight initially each other and then later, united under Antony Rogers leadership to fight against the oppressing Chinese. The Chinese themselves are armed with disintegrator rays. The novel became a great success followed by sequels, comics, TV show, film and a line of kids’ toys. The first two kids' toy guns of the Rogers franchise were the XZ-31 & XZ-35 rocket pistols. Later on the franchise as most of the SF genre reject the American rocket gun in favor of the Chinese ray gun and as the franchise evolved our brave Antony now “Buck” Rogers got the memo and switch to directed energy weapons as well. As a final act of defiant the rocket gun did leave its mark for decades after, the slime & slender silhouette of the rocket pistol became the recognize layout for any energy blaster and laser pistol we know today.
As Buck strapped a disintegrator pistol the rocket gun went underground dormant till the appearance of the Gyrojet in our real world. The Gyrojet appeared in a few movies and books. MBA eager for publicity even tried to draft Gene Roddenberry to place their newly rocket gun in Gene's newly Star Trek television show and though Roddenberry liked the Gyrojet, he didn't include Gyrojet in his show, futuristic as it been Roddenberry still prefer ray guns in his setting over rocket guns.
The sudden interest in rocket guns spark by MBA's products was short-lived in most forms of media with the exception of SF Role Playing Games. Within both pen and paper and tabletop RPG, there is usually Gyrojet or its equivalents around and if it "space" RPG, it is a "must have" weapon for the setting. From the early entry of Gyrojet in 1977 Traveller, to Battletech to the current Warhammer 40,000 Bolters, the jury had decided – rocket guns are here to stay! The reason of why RPG writers and player cling to their rocketeers so steadfast I could only guess at . The first answer could be the dissuasive role Traveller has on the genre of SF RPG as every new game afterward rips the progenitor for any good idea. Second, as MBA PR machine tried push their Gyrojet they propose it as the ideal gun astronauts can carry with them, a rocket pistol for the rocket age. 
That claim infiltrate to common consensus this idea that rocket guns are the only guns workable at the highest frontier. A common, yet forgivable mistake is the notion that recoil could be a dead killer in the null G of free fall combats where a single shot of regular slugger will launch the astronaut to infinity, truth is that the recoil of a gun isn't that devastating and personal maneuver unit could easily counteract the recoil. The other non- forgivable mistake is the naïve claim that fire requires oxygen and there is no oxygen in space so FIREarm couldn't work there but rockets could… the fact that both rocket and cartridges contain their own oxidizer slips there mind. The last possible reason for the abundance of rocket guns is that RPG combat is usually low on details. 
You may think this a strange comment giving the large variety of weapons the players and NPCs can wield and aim at each other but in reality unlike video games the difference between long rifle and phased plasma Gatling confine to the number of dice thrown for hit point, different ranges, loading time etc. the audio and visual details of such combats are part of the players imagining. Gyrojet and its equivalents can be used to spice the weaponry options and more important the tactics players have to face. Those futuristic Gyrojet have lower velocity and damage at close ranges and heavier toll to the target at longer distance opposite to regular guns. Such feature force Gyrojet wielders and their targets different moves as the targets try to close distances fast (rush attack) and the brave rocketeers try to keep that distance.                  


The MBA Gyrojet Weaponry from You Live Only Twice (1967)
By far, whenever you Google the term "Gyrojet".  the top search results be this 1967 James Bond movie starring the legendary Sean Connery as 007. This popular movie brought the Gyrojet and MBA to the world publicity and till this day Gyrojet is synonymous for "spy gun". In the movie, the variety of MBA's Gyrojet family were on display and were used by Tanaka's ninja army against Ernst Stavro Blofeld and his SPECTOR secret lair. Both pistols and carbines were presents and used. The deadly rocket-firing cigarette could have easily been small Finjet or Launchjet, though never referred in the movie as such and there was no such MBA's gadget buck then. From one early movie concept art it appears that the script included also the MBA's experimental volley gun and the 'survival Gyrojet pistol' with the spear-like Launchjet but those never make it to the screen.        

MBA Gyrojet Weaponry from Murderer's Row (1966)
It was 1966, two years after the Goldfinger movie hit the cinemas and become a financial success and make many production companies took noticed and tried to ride the spy-flick wave, Murderer's Row aired and let remind you one year before Bond feature a Gyrojet. It was survival Gyrojet pistol and it fires those Launchjet spears to threaten some hot chick to force her father into submission. The movie also included a volley gun similar in shape and function to MBA's volley gun and the same rocket-in-a-cigarette.

The Gyrojet Pistol from Collision Course (1989)
A barely heard movie from the late 1980's that include two rare items: Gyrojet pistol and no other than Jay Leno and Pat Morita! Jay Leno plays a detective bent on solving a murder case where the murder tool was Gyrojet pistol which is pretty amazing for movie made in 1989! The Gyrojet described to Leno by a policemen on the crime scene as "undetectable gun" cause there no forensic fingerprints. This "movie" was made at a time when buddy-cop films were popular and before Jay Leno got The Tonight Show.     

Outer Space MBA Gyrojet Pistols from Moon Zero Two (1969)
If Gyrojet is the ultimate space gun and wheel gun is the gun of the Wild West, what gun will the protagonists and their foes carry in this self-described "first space western"? Well, it would be the Gyrojet pistol of course with small attachment glow to it the make it resemble revolver, naturally.  

The Rocket Pistol from Runaway (1984)
In this almost forgotten film, written and directed by none other than Michael Crichton, one of the bad guys, Gene Simmons of KISS, is armed with a pistol firing miniature heat seeking missiles. Those missiles can lock to someone individual heat signature, flow and chase moving targets, avoid obstacles in their way and finally heat the target and explode.  

The Rocket Guns from 2149 from the Buck Rogers Universe

Buck Rogers appeared first in Armageddon 2419 A.D. back in 1928 as Anthony Rogers, WW1 veteran. Exposed to mysterious radioactive gas during mine survey he fallen into a suspended animation sleep to be woke up 492 later. The world was change as the Hans attacked and occupied America long time ago. The Chinese controls the cites as the remaining Americans live in the woods in tribes. The Americans are armed with rocket guns, a light simple tubes that fires rockets. First encounter this rocket gun, Rogers is baffle at its lack of recoil combining with his know how of 20th century firearm recoil management lead his missed his first shots as the rockets hit and explode too low on the ground near the targets feet. Later on Rogers how accepted into one of the gangs after saved one of its member, Wilma Deering, educated the 25th century Americans some 20th century old school gunnery knowledge that the somehow forgotten over the centuries like the advantage of indirect fire as the rockets can move in arched trajectory while the Hans' Dis-rays are a line of sight weapons, that firing from cover is the way to go when your guns are quiet and without any muzzle flash and so on… all helped the Americans gangs to unite and push the Hans back to China.             

Various Gyrojet weapons from Larry Niven Short Stories
Some of Larry Niven early short novels include Gyrojet pistols in the hands of the protagonists. In The Alibi Machine for example Gyrojet pistol is the tool of one murder that the new technology of teleportation is help to cover up.

"The Monster Wheel Affair" from The Man from U.N.C.L.E #8.
When a gigantic mysteries wheeled shaped space station appeared suddenly at orbit and it's the job of U.N.C.L.E. secret agent Solo Napoleon  to investigate it. Both Gyrojet pistol and Finjet in a cigarette were features in the novel. Published at 1967, the novel drew those two weapons directly from Bond's You Live Only Twice aired that same year.  

The Recoilless Weaponry from Caliban's War
In the universe of The Expense fighting a gun battle in null-G requires a recoilless handgun, firing a self-contain rockets, such gun apply no thrust to its wielder which is great when the Epstein Drive is off line as well as your magnetic boots.    

Accelerator rifle & rocket pistol from the Traveller RPG Universe
The proto-ancestor to most if not all Sci-Fi Role Playing Games, this 1977 published RPG had among many other weapons the an rocket pistol and automatic rocket launcher called ' Accelerator rifle' designated for zero-G combat, those rocket launchers firing rockets with minimal velocity and damage at point range but deadly at medium and long one. An variants of those rockets guns reincarnate in other Sci-Fi RPG like Battletech, Star-frontier and Stars without Number as Gyrojets, Gyroslugs, Cone guns etc.

The Bolter from the Warhammer 40k Universe
Plagiarize from Traveller and pumped till saturation with steroids, the Bolter is the weapon of choice of the Imperium of Man against the worst scums of the universe and it is a beauty of hybrid machinegun and rocket launcher. As it fed by cartridges called bolts which contain mini-rockets as their bullets. The bolts fed from magazines and drums as the Bolter spew spent cases at one end and yowling internally exploding rockets at the other end.    
The Torgue Weaponry from Borderlands 2
The Torgue weaponry in Borderlands 2 are essentially rocket guns, from pistols to assault carbines to shotguns. All firing somewhat slower projectiles but with higher damage due to their explosive nature. The low speed of the rockets decrease the guns accuracy at long ranges and against moving targets.

Next on FWS Armory
Australia is a great nation and continent known for many things, ground-breaking game-changing revolutionary weaponry and weapon technology is usually the first thing came to mind. Yet, in the early 90's one Aussie name James Michael O'Dwyer found weapon R&D firm called Metal Storm Limited to the develop and produce a line of guns under the brand of Metal Storm. Those guns were based on controlled electronic ignition of superposed rounds serially stacked in a single barrel. A few PR friendly documentaries populate the technology alleged high ROF as the 1 million round per minute supergun. The company went under a few years ago leaving behind a lot of interesting concepts, prototypes, plans and CGI presentations but no real military or civilian buyers. Next FWS Armory blog we shall go deep under to sort the true form fiction regarding that company from down under and its superguns. So mates! Prepare your Vegemite jars next by and till next time – kill it with 1 million RPM!

Next Time on FWS...
Once last time into the breach, dear readers of FWS as we will be closing out our three-part serial on nuclear weapons and nuclear war with the final discussion over the relationship between science fiction and the bomb. We will be also discussing a number of sci-fi examples, how else nuclear weapons could be used, and using nukes in space combat. Join us next time in about two weeks as close out one of the hardest blogposts I've read written here on FWS.  


  1. A fine comprehensive article on Rocket Guns. I must admit that I learned quite a few things from this as I never really paid them much attention. Things like the Danish Voss Musket I never knew about.

    A fine article from you both. I look forward to more.

  2. laser cut jet nozzles.
    mass production problem fixed

  3. I have to disagree on the crime an terror angle, because regular guns, don't require advanced metallurgy, and the rockets would still be expensive

  4. First off, thank you very much for this article. I have long been a fan of the Gyrojet just because of how interesting it was, but I always considered it a dead-end as a technology. However, your ideas for future applications have changed my mind on that! While I doubt we'll ever see much of the rocket gun, I credit that to how invested we are with conventional guns rather than any lack of merit of the technology.

    1. Second, since I'm very excited to hear your thoughts on Metal Storm, I have a few thoughts of my own should you be interested.
      The benefits seem to be the lack of moving parts which might cause a malfunction, as well as the degree to which the weapons are sealed from the environment (which, as the good fellows at InRange TV have shown, is one of the main considerations when it comes to reliability in adverse conditions), combined with the potential for higher capacity or rates of fire than some current weapons.
      Downsides seem to be that capacity is dependent on length instead of height (which may or may not be a bad thing, depending on the weapon), that an increased number of barrels increases weight, and that the effective barrel length changes with each shot.
      I believe that the change in barrel length can be compensated for by adjusting the amount and burn rate of propellant for each round in order to generate the same muzzle velocity. I also think that, for those worried about failures in electronics, while those fears are not unfounded, we have come a remarkable long way in the military use of electronics (with some optics being expected to outlast the rifle they're mounted to) and expect things to only get better.
      I have a number of ideas regarding weapon and magazine design for Metal Storm systems, which are available here if you are interested (http://luke-man.deviantart.com/gallery/). Either way, I look forward to your next installment of this series.

    2. Happy to hear you liked my ideas and concepts! Good job you did with the drawing of deviantart!

      You right about the advantages and disadvantages you listed, all of those and more will appear in the advantages & disadvantages segment of the article.

      With your premising I might copy some of your drawing to the Realistic Configurations segment...


    3. Go right ahead, I'd be flattered. I look forward to reading your ideas on the technology.

  5. Interesting concept from the '70's - a combination of rocket ball,rocket and shot shell:

    1. Couldn't read from the link, but I found these two:

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  7. My novel's heroine needed a gun that was small, light, lethal at close range but has a long reach.

    My idea was to turn the rocket inside out by wrapping the "neck" of a mortar shaped bullet with a gear-shaped block of propellant. The gear shape produces a high burn rate at launch for close range lethality and a slow burn rate after launch to overcome drag. The bullet's head plugs the barrel, the fins align it (and allow the rounds to be guided) and the "neck" doubles as an aerospike nozzle.

  8. I wonder if this weapon will wind up an a future World War II video game shooter?

    Take a look at this game, then get back to me:

    Sniper Elite 4 - Deathstorm Part 2: Infiltration: https://m.youtube.com/watch?v=dInqJ5tDGSg&feature=youtu.be