Remaking 1960s GYROJET Rockets - Part 1: Improvements

I've been working hard on bringing the Gyrojets back to life. I'm sure most of you already know about them, but in a nutshell they were tiny rockets invented in the 60s that were supposed to have a ballistic performance similar to that of a 45 ACP. Needless to say, they were a complete failure, and nobody has ever tried anything similar again. Until now 😎. In fact, the original design really left something to be desired, under many points of view which are covered in detail in the videos. I've made this topic into a 3 part series, with all 3 videos uploaded at the same time, covering as many aspects as possible. Not only will I be exploring a very interesting subject, that of rockets, but mostly I'll be trying to answer one question: if it had been designed properly, would the Gyrojet really stand a chance?
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[@jhonatancock2302]

Every day we get closer to the bolter, Praise the Emperor!

[@korbetthein3072]

Fire some of these babies out of one if those Fostec shorties and we're getting somewhere.

[@BolinFoto]

For the Emprahhh!

[@timulbrich954]

Needs a kicker stage i think, to make it capable at short range, give it some initial spin stabilization etc. and then the main Rocket engine fires. No idea how well that would work in reality though

[@korbetthein3072]

@@timulbrich954 It would prevent exhaust buildup in the barrel. Other than that, I think it would be really inaccurate, finicky, and unreliable. Can the rocket even survive the acceleration?

[@MaryGama]

.75 caliber bolters use a conventional bullet case with the initial charge that ignites the bullet. Also was rifled to get the initial spin up. Need to increase the size of the round, of course then it breaks your arm when you fire it.... But... THE EMPEROR PROTECTS!!!!!

[@GadgetSteelmare]

This man is out here trying to bring bolters to life and I am ALL for it.

[@BloodRaven744]

Get this man the proper funding and patents now!!!

[@sneedfeedandseed2410]

them imperials need to watch their backs, at this rate our bolters will actually be better than the ones they use. we already kind of have guns that are stronger than bolters. granted, those guns can't be fired by normal people and have to be mounted on vehicles but neither can bolters.

[@GenScinmore]

lol the new propellant looks like a swiss roll. very impressive work you've done with all this

[@Backyard.Ballistics]

the devil's swiss roll😉

[@ARockyRock]

Wonder how it tastes?

[@kingmasterlord]

@@ARockyRock **racks 12 gauge** Is that so?

[@ARockyRock]

@@kingmasterlord mmmm tasty high velocity metals

[@kingmasterlord]

@@ARockyRock piping hot #fresh

[@SollowP]

The Emperor smiles on your success. May the Omnissiah bless you future work.

[@Constable_Bob]

Awesome! The gyroget reminds me of those terrible animations of an entire pistol cartridge being fired out of the gun barrel…. but with some sweet science!

[@Helperbot-2000]

Youre right haha

[@aaronschmidt169]

If you made them so they'd fit tightly in a 12 guage rifled slug barrel and make a copper jacket on them I bet they would be pretty accurate, pretty cool though, thanks for sharing!

[@bobbm1]

would it be possible to just shoot it out of a shotgun? i mean all you need is a tube

[@korbetthein3072]

@@bobbm1 But would it be stable?

[@bobbm1]

@@korbetthein3072 I know nothing about rocketry or ballistics, so take what I say with a grain of salt, but if the barrel wasn’t choked and the ammunition was of the proper diameter I don’t see why it wouldn’t work

[@korbetthein3072]

@@bobbm1 Ballistics is a strange science, and you never know what might happen.

[@bobbm1]

@@korbetthein3072 exactly

[@nexusofice9135]

It seems like deployable fins would be a really cool improvement

[@Dodo-ze5ep]

0:40 The projectile had left hand rifling, the gun had right hand rifling. That's weird in two ways because 1911's usually have a left twist, so the gun is also wrong depicted. On top of that, the animated projectile seemed to have grooves from a longer twist rate, because the angles don't match.

[@saskafrass1985]

It just looks wrong as you watch it. Looks a a slipping worm gear. Still, nice clip.

[@tigeriussvarne177]

You made the first Bolter round! Praise the Emperor! Ave Imperator, gloria in excelsis Terra!

[@janhulek785]

"...and the MBA gyrojet became a forgotten weapon. Quite literally." [Next video starts with "credit: forgotten weapons"] Lol

[@jameshealy4594]

You continue to bring a unique style and more importantly, information that puts you in the very top tier of firearms-related channels. Keep up the great work my friend, you'll go far with content of this quality.

[@timbrwolf1121]

I actually redesigned the gyrojet nearly a decade ago. Mine was a hybrid 50 caliber. Basically a rocket in a 50 BMG case with enough powder to engage the rifling and let the projectile leave the barrel level. With the hope of being lethal at point blank range which the gyrojet was not. The kicker of my design is that it was scaleable from at least .50 all the way up to 5 inch naval guns. Required zero modification to existing weapons platforms. Actually a couple years after I shelved my design DARPA issued a request for a way to extend the range of armaments from .50 up to the 5inch. I just have no financial means to further my design.

[@PaulieMcCoy]

You should release your information to FOSSCAD or are you interested in machining, additive machining, ballistics, physics at large? FOSSCAD is mostly additive manufacture but I feel like the community needs to diversify out of 3d printing stuff and do more interesting stuff. Just a thought. Cheers.

[@Barskor1]

Please don't be a hoarder if you can't use it let it out to be free and know you did that when you see all the vids and Congress Critters shitting themselves to ban it.

[@vazione5410]

Share if possible, im sure people will help make it happen 😊

[@Backyard.Ballistics]

This is Part 1 of 3 of my video series on the Gyrojet. You can find the other two parts at these links: Part 2: kzbin.info/www/bejne/j6fRe2SojpiNd5I Part 3 (on my second channel Beyond Ballistics): kzbin.info/www/bejne/aIGsc4R5qL6inc0 you can order Mel Carpenter's book on the gyrojets at this link: www.gyrojet.net/

[@GadgetSteelmare]

You may want to pin this message so it doesn't get buried!

[@DSlyde]

This channel was always an underrated gem but replicating and improving gyrojets? It's like it was made for my interests

[@rod4309]

YES! I'm glad someone's interested in doing this.

[@piropitiflautico]

When somebody says "forgotten weapon" *insert clip of Ian pulling concealed shotgun and shooting you*

[@MildMisanthropeMaybeMassive]

My teenage mind always thought that the gyrojet would have had success as a two stage system where it’s first fired out of a conventional cartridge with gunpowder and then the rocket activates, ideally only after it had crossed a certain distance to extend the range.

[@Preyhawk81]

that would be an Bolter :)

[@giacomodalmonte318]

now i have the inspiration to build my personal bolter gun

[@SSGTWinters]

congrats you just made a bolter shell from warhammer 40K

[@jeffyates4813]

Try a hybrid of a conventional bullet with the gyrojet. Half of the barrel for the blast of the explosive in the casing, then the other half for the projectile and sabot. The projectile would be surrounded by a separating sabot packing and the projectile would have spiraling fins with the rest similar to the original gyrojet projectile. It would be ignited like a tracer round. The conventional portion would give it starting velocity, and the sabot to give it initial stability through the barrel, which would be rifled in some way to initiate spin. After exiting the barrel the sabot would separate and the fins of the projectile would then stabilize it and make it accurate. What your video is doing is recreated the recoilless rifle which was developed for the Korean war and now used by ski patrols to control avalanches.

[@jameshealy4594]

0:40 I think the rifling being transferred to the projectile is twisting the wrong direction.

[@itachi999987]

Beat me to it good eye

[@kieranh2005]

You're looking at the near side of the projectile and the far side of the inside of the rifled barrel. So it's going up on the side that you can see (of the projectile), but down on the other side, creating the optical illusion.

[@jameshealy4594]

@@kieranh2005 The grooves are lower at the front and higher at the back, given rotational direction they should be the opposite. I'm quite sure that I'm correct but if you don't think so, what is the mistake he mentioned in your opinon?

[@Helperbot-2000]

@@jameshealy4594 you have to remember that youre seeing the rifling on the other side of the bullet. Looking from the back the rifling is clockwise, and so goes the bullet

[@jameshealy4594]

@@Helperbot-2000 I think you're the one not seeing it correctly mate but I have no easy way to prove it to you beyond some asinine argument like "I got the heart". I find it really helps me visualise it if I think about only one point in the barrel and imagine the bullet passing through that point. It becomes quite clear that the rifling is RH twist and the engraving on the bullet is LH twist.

[@TimeSurfer206]

At 4:10 you wandered into the exact same thoughts I had when I was a kid, and was watching the Hoopla at the attempt to make them viable. My first thought was, "Why a Handgun? WHY SINGLE SHOT?? _This is a barrage ammunition._"

[@prjndigo]

A pair of canted roller rings (three each) in the first part of "barrel" travel that would start the spin from the initial forward movement of the projectile would be a MAJOR improvement in the design of the weapon.

[@captainchuck483]

using rockets in a firearm instead of more conventional projectiles is one of those ideas that seems like it would be promising but in practice usually falls flat

[@lalinowl]

SuckBoyTony's design looks promising. His design uses the same concept as a rifled slug.

[@DeltaPi314]

T-90: Am I joke to you?

[@garywheeler7039]

My understanding of the original gyrojet, is that the first part of the propellant burns especially fast, then a slightly slower burning propells it along to maximum speed. The first impulse makes it leave the barrel fast and in a straight line.

[@BacklTrack]

Analbanian

[@lordfrostdraken]

Only because it needs more refinement, ever heard of the rocket propelled rounds the military is testing for their 155mm artillery guns? Same concept just bigger gun.

[@karansingh1154]

0:40 is it me or is the bullet rotation out of sync with the rifling?

[@spencerknowlton1555]

It's spinning in the wrong direction

[@aaronhammond7297]

Spinning right direction, groove on bullet is sloping wrong direction

[@chemistryofquestionablequa6252]

I've considered remaking these, but it would be prohibitively expensive for me. Awesome to see that you've done it, that's a lot of work!

[@TixenDotNet]

That bit about the grain size of solid propellant is also apparently why you're not supposed to shake cartridge ammunition much: it causes the gunpowder grains to break down which increases pressure and can cause explosive malfunctions

[@TrueSighted]

Personally, I can see the rocket ammo as a sustain kind of ammo, for instance if you wanted to have a round that could push threw a liquid, like a round that could travel threw water at a distance. However getting enough velocity would be tough under normal circumstances. Otherwise in air, at normal distances, I think it would be a detrement rather than benefit. That said, a combined ammo, with an initial pulse to provide velocity, and a sustained jet to provide both stability, sustained momentum and distance, might be an interesting concept with looking into. I dont see it being made a pistol round all that easy, but with a rifle or shotgun, that has the longer cartridge to work with, it might be possible to come up with something. or even a bullet with pulsed delays that added a bit of spin, and thrust as set burn rates, and delays, to allow the bullet to travel farther and straighter, for longer. It might be worth examining. Could be doable. Couldn't over do it though, or you'd risk changing trajectory rather than stabilizing it; but in a sustainable low power pulse, it might be interesting. Might have to build in a control interface if its a rocket thats more sustained and powerful. Would depend on what you wanted to make it do. But interesting regardless.

[@mbgdemon]

This is amazing! Please keep working on it---from watching your videos, it seems like the addition of a properly sized barrel alone would make for a decently effective practical device.

[@bobthompson4319]

I wonder how a rocket assisted projectile would work in this form. They work in tank main guns and where going to be the gun on the overly expensive Zumwalt destroyers. So I wonder if you could use them in like a .338 or .50 and have it delayed to where it ignites before the projectile noses down to make it go farther????? Would be an awesome experiment.

[@sebbes333]

*@Backyard Ballistics* (hope you see this eventually, I am apparently 2 years late to this party) :/ About the slow acceleration, what if you make a conventional charge in the bottom, that burns up & also ignites the rocket? In that way you "SHOULD" get the best of both options? Like this: end cap with igniter ➡ [ acceleration_charge |=| ⬅ Gyro_jet_base_plate. (acceleration_charge_area) > ⬅Ballistic_end-cap

[@Veritas419]

Great work! Entertaining and informative.

[@maxdelaserna9540]

This thing is absolutely amazing!!! Very nice video, great topic and very good content. Really nice

[@imstupid880]

Kind of crazy MBAssociates was based in San Ramon, didn't think a piece of gun history would be so close to home

[@rickoshea8138]

Video was worth the wait since the last one.

[@jamesclark6420]

A fascinating project and evaluation. Gyrojet was a little before my time. I didn't get to this world until 1972. But I've been hearing about them in gun magazines and books as long as I can remember. There's a very interesting article and test firing that was done by Small Arms Review magazine in the early 2000s, which I have. Apparently some users loved Gyrojet, including our President Ronald Reagan. There was at least one pistol used in combat in Vietnam as a personal weapon, where it apparently performed very well. There was also a short barrel snub version of the pistol and some Gyrojet guns were select fire. Gyrojet rockets did apparently have a kicker in them to create initial acceleration before the rocket charge began to get it moving with sufficient velocity. The KZbinr TaoFledermaus also did a test of the Gyrojet pistol and carbine a few years ago with their original owner. There were actually two calibers. The first rockets were 13mm, but then reduced to 12mm after the passage of our Gun Control Act of 1968 federal law took effect. I've only ever seen one Gyrojet pistol in person, and that was in a museum. And I'm in the firearms industry! That's how rare they are even here in the United States.

[@thinman4648]

This is like a war hammer 40k bolter, except the bolter is about .98 caliber and has a kicking chard of gunpowder for the initial acceleration and cycling the gun, then the rocket charge fires accelerating it faster, then it burns out. Think rocket assisted artillery but “hand held” explosive payload included

[@janhulek785]

Oooh yeah! The sweet sweet science is back better than ever with it's long awaited project! Now let's learn how it works... :)

[@sicotronicypunto7460]

That's an absolutlly awesome idea, so exited for the other parts ^^

[@greggv8]

A large part of the Gyrojet's inaccuracy was the roll crimp was often too large and rolled over the edge of one or more of the nozzles. The Coanda Effect would cause the exhaust to curl around the rolled edge and produce an angled or sideways thrust. They never got into automated mass production of the ammunition. In addition to the lathe turned propellant grains, the nozzle plates were hand drilled one by one using an angled turret on a drill press. The bits were specially shaped to form the tapered nozzle holes and frequently broke. To control the burning speed of the propellant the outside of them was sprayed with white latex house paint.

[@yesterdayschunda1760]

This man is out here making Bolter ammunition

[@earthman4222]

Clear explanations and logic. Subbed based on this first video. I enjoyed the hell out of this.

[@garywilloughby6893]

This is very interesting thank you for posting this video

[@Rutherfordium2023]

The gyro slug for the gyro shotgun would be amazingly cool, although I don’t know how you would do an actual load, so restricted to just slugs it would be more like the gyro blaster.

[@flameendcyborgguy883]

Me: GYRO JET REVOLVING CARBINE! Also, Am I only one who would put a Gyrojet type unit into normal shell, such that burning of initial ejection material causes the ignition of the internal propelant?

[@someguy2741]

You may want to watch the rocket videos on Tech Ingredients channel. He also deals with ignition and different grains and chemistry.

[@DC_DC_DC_DC]

Up

[@Sawer]

Boy i love this channel

[@NorthernMafia8]

Brandon will be needing some after his video

[@hunteraltman4762]

I was hoping these would come back someday!

[@BoraHorzaGobuchul]

I hope to see a full-auto 50cal gyrojet in my life yet!

[@JohnDoe-rx3vn]

If balancing the thrust is an issue, you could use one port that leads to a small chamber, then two ports

[@AHumanIAmNot]

The rifling in the animation was right hand but the striations imparted on the bullet by the rifling was left hand.

[@berryreading4809]

nah that was just reverse rifling 🤣

[@mariosebastiani3214]

Nice bow to Forgotten Weapons!

[@randominternetuser2888]

There was a stacked rocket system called "Hellfire" I believe. Not sure if they ever made it fully hand held bit it's out there.

[@ToninFightsEntropy]

If they started with at least a little bang, and the rest of the fuel was for fizzle, low exit velocity's not such a problem.. if the nozzle is packed and covered and can survive a bang, or if a nozzle with a hole to the rest of the fuel is what forms from a composite from an initial reaction that makes the bang, you've got 2 in 1. If the reactory materials that do the start bang are a thinning circle towards the middle, maybe you can get some kind of resulting bell curve shape that starts thicker at the outside, to a thin pointed gradient, and adjust the curve of packing thickness towards the centre to modify resulting nozzle shape). Now add PCB servos inside for a pointy fin at the front to angle the projectile via a tiny radio receiver, or a preprogrammed flashed-on-fire microchip, to function like a gyro, from lidar data off the gun-sight. Also, less bang at the start means more turning power before it's up to speed. And this is how you make the Zorg ZF1 Replay Button.

[@pinjohnston3706]

Amazing

[@SupremeShuckle]

Oh boy. This could be huge. If you’re able to streamline it there’s big money on the table

[@reuben87331]

If you're redesigning the gyrojets completely, you could add a launching charge similiar to a RPG. The projectile ins't very large, so it wont need much to get it out the barrel. You could just recess the nozzle into the body, then put in a launching charge and put some ignition powder in the nozzle ports to start the jet once it has launched. In theory you could also use this to keep your barrel shorter, albeit with some backblast.

[@123456789yeti]

Honestly a primer for a large caliber would probably be sufficient

[@dutch_asocialite]

I tried this a while back, trying to make a modernised version of the device for my alternate reality world, but... well, fell short when I realised I had no idea what I was doing because I had no idea how rockets work. So thanks for this, if I ever revisit that world I'll be sure to discretely credit you when I plagiarise this.

[@mathewpankratz5767]

Instead of creating the spin with the nozzles and losing performance why not rifle the barrel? Or is the increased friction more costly than the loss in performance?

[@Fat_Ninjah]

Can the rocket be ignited like a tracer? If so, wouldn't launching it from a 12gauge shotgun give it the initial velocity boost needed to be lethal at close range, mitigating the shortcomings of the original Gyrojets?

[@GundamReviver]

-mumbles "this would also make it more bolter like yet again" -

[@africanelectron751]

The emperor approves.

[@lyncharles4856]

Finally, someone did it

[@Levy7S]

thank you

[@RETOKSQUID]

Switch to a non angled nozzle, and add folding fins. Also might look at using a booster charge of powder behind the projectile to start the sequence of the launch.

[@draconian6692]

If you could combine traditional bullet design and have rocket propulsion to increase velocity would be epic

[@dicedoomkid]

@Backyard Ballistics You should contact Explosions and fire on KZbin about a propellant option. Also I think it would be cool to see this in a long range rifle, where the rocket has the range to use all of its fuel, thus getting the most of its potential energy.

[@vyor8837]

Maybe have a two stage propellant? One that goes off similarly to a normal bullet and then the rocket part?

[@lordfrostdraken]

The Holy Bolter cometh Brothers!!! FOR THE EMPEROR!!!

[@ethanspaziani1070]

YES

[@frostedfur]

I have a Gyrojet round. It's one I'm hanging on to.

[@kanepoholko8799]

Got it! 😮

[@michaeldougherty2807]

You should talk to Brandon Herrera, he has one of the original ones

[@scar3xcr0]

I wanna see a company produce and sell gyrojet 12 gauge slugs, That would be cool!

[@JinKee]

THIS IS SO AWESOME! I am all for modern CNC and 3d printed gyrojet ammo. combine this with that laser guided .50 cal DARPA projectile and you'll have a real winner.

[@greydonstautzenberger3901]

Keep it up

[@topsecret1837]

If you redesigned the launching equipment to essentially make a rocket launcher, what was the point of this project in the first place? A gun could have some means of firing these rounds; they just need a means of stabilizing themselves in flight.

[@JinKee]

4:17 A weapon to surpass Metal Storm.

[@robbytheremin2443]

There's a KZbin channel called Tech ingredients that has a wealth of information on rocket propellant formulation. Pretty cool.

[@Backyard.Ballistics]

I'm already a subscriber! They do hybrids though, not good for high accelerations

[@hobbitmansstash]

Nice

[@Ulrich_dArth]

Imagine winning the 'Nam with these

[@Chrisspru]

a gyrojet- shotgun hybrid might work well. overcomming the initial speed and accuracy issue with a conventional gun design, with the jet kicking in mostly past the barrel. basicly how an rpg7 launches, but in a closed rifle design. the shotgun powder load can be relatively low, as to reduce recoil. yes, that would be a bolter.

[@lungshenli]

MR. TORGUE LIKES THIS

[@Bladsmith]

Where did you get those patent drawings? I'd like some for my new home.

[@Backyard.Ballistics]

You can by the prints off Etsy, and then use the frame you prefer.

[@giuliobellucci3604]

It’s a great idea all the project, but in rockets the diverging part needs to be in relation between the pressure of the gases that escapes and the “expansion” of the diverging part, so at the exit of the rocket the exhaust needs to be at the same pressure of the atmospheric pressure to have a supersonic exhaust so if I make just a bigger expansion in the diverging part it does not mean that I will have more thrust, to have more thrust I need to have the perfect relation between pressure of the exit gases from the rocket and atmospheric pressure

[@cheesehead_man1375]

What about a bullpup style rifle (with the magazine behind the trigger)? The shoulder mounted style just seems like another rocket launcher but without the explosives to me

[@colinmoore7460]

Rocket propelled shotgun slugs? I like it!

[@sniperfuazo6495]

would like to have a more of a hybrid system where the gyrojet is pushed by initial powder like a normal bullet would but instead of pushing to over 400m/s velocity it only pushes about 200m/s or so..just enough to make up the range which if it is harmless before (when there is only the gyrojet it self)

[@gruberstein]

Look into machinable ceramic for the nozzle.

[@innacrisis6991]

1:36 There's another that comes to mind, the LOSAT (Line Of Sight Anti-Tank) missile, a KE penetrator in missile form. Admittedly, not man-portable, but an honourable mention nonetheless

[@anthonywilliams379]

it may have been better to use a thicker machined hull with an increased mass at the nose, then thread the tail section in order to screw the nozzle section into it, this would both allow the projectile to maintain stability and lethality at range as well as potentially make them reusable if they survived, additionally it would also allow for much more volatile propellant to be used.

[@theeggman1199]

Next do volcanic rocket ball!

[@ravensshadow2179]

I also wonder if firing these out of a rifled shotgun would have solved the problem with the low muzzle velocity and stabilization.

[@chainsawchanselour5452]

Now make explosive tips for irl bolter

[@centurybeats9330]

Was the mistake in the animation the lack of the little groove in the bullet that contains lube necessary for the bullet to exit the barrel while still being tight against the rifling?

[@zpinkney34]

The rifling should be spinning the projectile in the opposite direction in the first animation

[@EmeraldForester777]

Add a warhead and BOOM! Micro-missiles

[@hellishgrin4604]

Anyone know if it's legal in the US to turn an inert LAW launcher into a model rocket launcher? Or does it need a for 1 because it was a weapon at some point? To be clear I don't want to reactivate it, just make a novelty or prop.

[@jimmehjiimmeehh9748]

I didn't get notified of your uploads despite being subbed... How odd.

[@JoeMama-me5wp]

With the rocket pistal cab be easly transformed into a micro misle

[@user-596]

Rocket propelled bullets is such a 60s/space age idea.