9 ms·

Centrifugal Machine Guns

96 points by smacktoward 7y ago

wiggler00m 7y ago
It wasn’t until World War One that the concept began to be considered again. In June 1918, Major Edward T. Moore and Saul Singer filed a patent for a centrifugal machine gun powered by an electrical motor (US #1,332,992). The motor spooled up the centrifugal barrel assembly to rotate extremely quickly and impart centrifugal force on projectiles. According to Julian Hatcher the gun could fire steel ball bearing projectiles at approximately 1,200 feet per second. Fire was controlled by a stop pin in the ammunition feed tube. Moore claimed the weapon could fire a projectile 1.5 miles with enough force to kill a man. He also suggested the weapon’s rate of fire approached 2,000 rounds per minute. It appears that Moore’s gun may have been tested in 1918 but Hatcher described its accuracy as ‘extremely poor’.
- 6nf 7y ago
  Modern bullets are not spheres because spherical projectiles don't want to fly straight, especially when you impart a bunch of spin on them first.
  - DrStalker 7y ago
    I imagine such a weapon would be more of a suppressing fire tool than something intended to shoot accurately.
    - rocqua 7y ago
      You still need some accuracy for supressing fire. Especially in the vertical direction. You might wanna keep a horizontal line saturated with lead, but vertical dispersion of targets is usually much lower.
      - jbms 7y ago
        Turn it sideways 90 degrees.
  - notduncansmith 7y ago
    It's true that the spin from a centrifugal gun is unlikely to make bullets fly straight, although ironically "impart a bunch of spin on them" is also one of the foremost techniques for making bullets fly straight: https://en.wikipedia.org/wiki/Rifling https://en.wikipedia.org/wiki/Rifling > In firearms, rifling refers to the helical groovings that are machined into the internal (bore) surface of a gun's barrel, for the purpose of exerting torque and thus imparting a spin to a projectile around its longitudinal axis during shooting. This spin serves to gyroscopically stabilize the projectile by conservation of angular momentum, improving its aerodynamic stability and accuracy over smoothbore designs.
    - catalogia 7y ago
      Relating to spinning spherical projectiles, some airsoft guns impart backspin on the spherical plastic pellets they fire to flatten their trajectory: https://en.wikipedia.org/wiki/Hop-up_(airsoft) https://en.wikipedia.org/wiki/Hop-up_(airsoft)
  - pzs 7y ago
    It's called the Magnus effect [1]. I learned about it from my wife, who learned about it when she did a tennis instructor course. [1] https://en.m.wikipedia.org/wiki/Magnus_effect https://en.m.wikipedia.org/wiki/Magnus_effect
stevenhuang 7y ago
I wonder if such a weapon could be feasible given the affordance of modern technology. Very steam spunk, if so. Not to say I condone such matters, but curiosity wonders the same.
h2odragon 7y ago
not high velocity, not high accuracy, but they can be effective. small prototypes capable of delivering a withering stream of BB's are well within the capabilities of the misguided teenager.
- pontifier 7y ago
  Sounds awesome :) Are you speaking from personal experience?
  - lightedman 7y ago
    We had centrifugal pellet guns at roadside carnivals 30+ years ago, glass bottles were the targets. You could barely hit the target from 25 feet away because the power simply wasn't there, and so many times those pellets simply ricocheted right back at you. Those got replaced with the more 'fair' and powerful tube/air-fed rifles which got used to shoot out a star on a piece of paper (which in and of itself is a bit of a scam if you don't know the trick.)
    - obituary_latte 7y ago
      The trick being to shoot around the star I presume? That’s the only “trick” I’ve ever heard of - curious if there is another.
      - tyingq 7y ago
        I believe it is a few things. Light finger to get single shots versus repeated. First few shots to figure out how bad the sights are. Shoot around the star until you have a good perimeter. Shoot the center to pop it out. Though you can find credible marksmen that know all this, yet fail to win. It's rigged.
        LinuxBender 7y ago
        It is rigged, but it's the paper targets (star diagram). The paper intentionally is strong enough that it is highly improbable that any bb/pellet gun will have the force to knock out the remaining 20% of the outline of the star no matter how accurate the shooter is. The inner part of the target will begin to fold on purpose.
leeoniya 7y ago
is it feasible to make an electromagnetic machine gun powered by a battery or bank of caps? it would have the same advantages - cheap projectiles, no gunpowder and mostly silent. there's also this: https://m.youtube.com/watch?v=oWEqyrKLz6M https://m.youtube.com/watch?v=oWEqyrKLz6M https://m.youtube.com/watch?v=AEu9LLQpOF8 https://m.youtube.com/watch?v=AEu9LLQpOF8
- spullara 7y ago
  They are called rail guns. https://en.wikipedia.org/wiki/Railgun https://en.wikipedia.org/wiki/Railgun
  - DrStalker 7y ago
    There are also coil guns, which present a different set of benefits and challenges than railguns: https://en.wikipedia.org/wiki/Coilgun https://en.wikipedia.org/wiki/Coilgun
- CoffeeDregs 7y ago
  Sure but it takes quite a bit of energy per shot. A fairly standard 7.62mmx51mm NATO shell puts out a bullet with about 4000 Joules of energy. That's roughly a 0.4F, 100V capacitor or 2,000 200uF, 100V capacitors (around $2,500) _per shot_. 20 rounds means that the gun has around $50k worth of capacitors and that's before we start talking about rapid-discharge/charge rate systems and energy transport. Once the electrical rail machine gun is built, the per-shot costs are pretty low (copper, lead, machining) and grid supplied energy (hello supply-lines), but then a 7.62x51mm NATO round is $0.42 (in volume). The rail guns that being trialed are monsters: not a whole lot of point in shooting a $0.42 NATO round when you have nuclear power generator to recharge the gun. By the same token, there's probably not a whole lot of point spending $100k per soldier to kit them with a barely portable weapon that is matched by a $2,000 AR-15 firing $0.42 mass-produced ammunition with a mature supply line and easy portability. But, yeah, I'd like to see them, too...
  - mlyle 7y ago
    Conversely, a base Tesla Model 3 puts out about 200kW sustained for longer than most machine guns fire a string; 5.56 NATO is about 1800J; a M16 fires at 13Hz; if your process is 100% efficient this is about a power demand of 24KW or about 1/8th of what the Model 3 draws from its battery pack. Incidentally, such a Tesla-machinegun would not be regulated as a firearm in many/most jurisdictions. > the per-shot costs are pretty low (copper, lead, machining) Bullets are not machined (except for exotic uses where insane accuracy is required-- 1000yd championships employing exotic chamberings and weapons, etc).
bradyd 7y ago
The Mythbusters built one of these. https://www.youtube.com/watch?v=Y3cRNEyUTF8 https://www.youtube.com/watch?v=Y3cRNEyUTF8
natmaka 7y ago
In a similar vein the H&K G11 also had ambitious objectives and was shock-full of clever ideas, however such beasts make the KISS principle (rather decisive for a weapon) difficult to follow. https://www.youtube.com/watch?v=QGKcvM2Hh4g https://www.youtube.com/watch?v=QGKcvM2Hh4g
- irjustin 7y ago
  Oh man, that video reminded me of Metal Storm[1], something I hadn't paid attention to since 2008. The idea seemed so cool to the college grad in me. Clearly there are problems with ammunition handling in actual battle situations and/or long term storage that probably made this a non-viable war machine similar to the G11. [1] https://en.wikipedia.org/wiki/Metal_Storm https://en.wikipedia.org/wiki/Metal_Storm
irjustin 7y ago
Love the idea from an absurdity aspect. Accuracy is very low, portability requires a vehicle, wear is quite high on the "outside" side of the channel. Feels as effective as a repeating shotgun mounted on a car.
- lightedman 7y ago
  "Feels as effective as a repeating shotgun mounted on a car. " Dunno, an AA-12 loaded with HE-12 explosive rounds mounted on a car or truck could be a very effective mid-range area of denial tool.
  - _djo_ 7y ago
    See the PAW-20 for an example of this taken to its logical conclusion.
    - dmos62 7y ago
      Good overview of PAW-20 https://www.youtube.com/watch?v=QHbqHx3TLBE https://www.youtube.com/watch?v=QHbqHx3TLBE
      - bradknowles 7y ago
        Wow. That was a wild hour-long trip down into weird and wonderful weapons! Thank you!
- Sharlin 7y ago
  I wonder just how low the accuracy was (well, to be a pedant, I presume the main problem was precision rather than accuracy). The 99% use case for machine gun fire (and indeed rifle fire in modern warfare) is suppression.
- KineticLensman 7y ago
  "Thank the Lord / That we have got / The Gatling Gun / And they have not"
aitchnyu 7y ago
I guess the lack of rotation of the bullet made it inaccurate?
chroma 7y ago
I'm rather surprised that there isn't more innovation in firearms. For example: Has anyone tried to build a rifle that fires inert pellets using a combustion chamber powered by hydrocarbons (say… propane) and an oxidizer (oxygen or nitrous oxide)? That would make ammunition much lighter and cheaper, eliminate the need for brass feeding/extracting mechanisms, and allow for "dial a velocity" by feeding different amounts of gas into the combustion chamber. Another possibility would be to have a belt that accelerates the projectile. The "ammunition" in that case would be batteries and inert projectiles. Like a propane gun, velocity could be customized for each shot by varying the belt speed.
- throwaway2048 7y ago
  Part of the issue with a design like this would be that storing compressed gases is very bulky and prone to catastrophic total failure (very bad for a weapon being abused by grunts). Gunpowder in cartridges already contains an propellant and oxidizer, and per mass you really aren't going to gain anything from going with a gas based system. Heat management would also be a huge issue, spent casings carry away a surprisingly large amount of heat, and even then most guns are unable to sustain continuous fire rates for long. This was a serious issue with case-less ammunition designs for instance.
  - donaltroddyn 7y ago
    Yeah, anyone who's had a brass casing land down the back of their neck can attest to how much water heat they draw away from the weapon. I also wonder how important the gas exchange caused by the mechanical cycling of the action is to cooling, as most modern rifles are pretty well sealed when in battery.
- GhettoMaestro 7y ago
  Some stuff gets pretty advanced. Check out the M134D. Sure it’s 1960’s tech, but it’s still amazing.
- rocqua 7y ago
  A nice thing about brass cases is that they also provide a really good seal around the breach. Especially because brass is flexible enough for the thoat to expand and seal against the start of the barrel. Any other gas based system needs to deal with keeping exploding gas from leaking out the holes through which you feed in new bullets.
nabla9 7y ago
DREAD from 2004 http://www.defensereview.com/world-exclusive-video-dread-weapon-system-devastating-jam-proof-and-silent/ http://www.defensereview.com/world-exclusive-video-dread-wea...
artsyca 7y ago
Centrifugal force is a fictional force it's due to centripetal acceleration https://en.m.wikipedia.org/wiki/Fictitious_force https://en.m.wikipedia.org/wiki/Fictitious_force
- shalmanese 7y ago
  relevant xkcd: https://xkcd.com/123/ https://xkcd.com/123/
tyingq 7y ago
2000 rounds per minute is pretty impressive. Though miniguns/Gatling do much better these days...6k/minute. And not terribly complicated in how they work. The concept fits mostly in one animation: https://qph.fs.quoracdn.net/main-qimg-e01cffa77db21231f6d9da19970d9ef3 https://qph.fs.quoracdn.net/main-qimg-e01cffa77db21231f6d9da...

96 points by smacktoward 7y ago

It wasn’t until World War One that the concept began to be considered again. In June 1918, Major Edward T. Moore and Saul Singer filed a patent for a centrifugal machine gun powered by an electrical motor (US #1,332,992). The motor spooled up the centrifugal barrel assembly to rotate extremely quickly and impart centrifugal force on projectiles. According to Julian Hatcher the gun could fire steel ball bearing projectiles at approximately 1,200 feet per second. Fire was controlled by a stop pin in the ammunition feed tube. Moore claimed the weapon could fire a projectile 1.5 miles with enough force to kill a man. He also suggested the weapon’s rate of fire approached 2,000 rounds per minute. It appears that Moore’s gun may have been tested in 1918 but Hatcher described its accuracy as ‘extremely poor’.

6nf 7y ago
Modern bullets are not spheres because spherical projectiles don't want to fly straight, especially when you impart a bunch of spin on them first.
- DrStalker 7y ago
  I imagine such a weapon would be more of a suppressing fire tool than something intended to shoot accurately.
  - rocqua 7y ago
    You still need some accuracy for supressing fire. Especially in the vertical direction. You might wanna keep a horizontal line saturated with lead, but vertical dispersion of targets is usually much lower.
    - jbms 7y ago
      Turn it sideways 90 degrees.
- notduncansmith 7y ago
  It's true that the spin from a centrifugal gun is unlikely to make bullets fly straight, although ironically "impart a bunch of spin on them" is also one of the foremost techniques for making bullets fly straight: https://en.wikipedia.org/wiki/Rifling https://en.wikipedia.org/wiki/Rifling > In firearms, rifling refers to the helical groovings that are machined into the internal (bore) surface of a gun's barrel, for the purpose of exerting torque and thus imparting a spin to a projectile around its longitudinal axis during shooting. This spin serves to gyroscopically stabilize the projectile by conservation of angular momentum, improving its aerodynamic stability and accuracy over smoothbore designs.
  - catalogia 7y ago
    Relating to spinning spherical projectiles, some airsoft guns impart backspin on the spherical plastic pellets they fire to flatten their trajectory: https://en.wikipedia.org/wiki/Hop-up_(airsoft) https://en.wikipedia.org/wiki/Hop-up_(airsoft)
- pzs 7y ago
  It's called the Magnus effect [1]. I learned about it from my wife, who learned about it when she did a tennis instructor course. [1] https://en.m.wikipedia.org/wiki/Magnus_effect https://en.m.wikipedia.org/wiki/Magnus_effect

stevenhuang 7y ago

I wonder if such a weapon could be feasible given the affordance of modern technology. Very steam spunk, if so. Not to say I condone such matters, but curiosity wonders the same.

h2odragon 7y ago

not high velocity, not high accuracy, but they can be effective. small prototypes capable of delivering a withering stream of BB's are well within the capabilities of the misguided teenager.

pontifier 7y ago
Sounds awesome :) Are you speaking from personal experience?
- lightedman 7y ago
  We had centrifugal pellet guns at roadside carnivals 30+ years ago, glass bottles were the targets. You could barely hit the target from 25 feet away because the power simply wasn't there, and so many times those pellets simply ricocheted right back at you. Those got replaced with the more 'fair' and powerful tube/air-fed rifles which got used to shoot out a star on a piece of paper (which in and of itself is a bit of a scam if you don't know the trick.)
  - obituary_latte 7y ago
    The trick being to shoot around the star I presume? That’s the only “trick” I’ve ever heard of - curious if there is another.
    - tyingq 7y ago
      I believe it is a few things. Light finger to get single shots versus repeated. First few shots to figure out how bad the sights are. Shoot around the star until you have a good perimeter. Shoot the center to pop it out. Though you can find credible marksmen that know all this, yet fail to win. It's rigged.
      - LinuxBender 7y ago
        It is rigged, but it's the paper targets (star diagram). The paper intentionally is strong enough that it is highly improbable that any bb/pellet gun will have the force to knock out the remaining 20% of the outline of the star no matter how accurate the shooter is. The inner part of the target will begin to fold on purpose.

leeoniya 7y ago

is it feasible to make an electromagnetic machine gun powered by a battery or bank of caps? it would have the same advantages - cheap projectiles, no gunpowder and mostly silent. there's also this: https://m.youtube.com/watch?v=oWEqyrKLz6M https://m.youtube.com/watch?v=oWEqyrKLz6M https://m.youtube.com/watch?v=AEu9LLQpOF8 https://m.youtube.com/watch?v=AEu9LLQpOF8

spullara 7y ago
They are called rail guns. https://en.wikipedia.org/wiki/Railgun https://en.wikipedia.org/wiki/Railgun
- DrStalker 7y ago
  There are also coil guns, which present a different set of benefits and challenges than railguns: https://en.wikipedia.org/wiki/Coilgun https://en.wikipedia.org/wiki/Coilgun
CoffeeDregs 7y ago
Sure but it takes quite a bit of energy per shot. A fairly standard 7.62mmx51mm NATO shell puts out a bullet with about 4000 Joules of energy. That's roughly a 0.4F, 100V capacitor or 2,000 200uF, 100V capacitors (around $2,500) _per shot_. 20 rounds means that the gun has around $50k worth of capacitors and that's before we start talking about rapid-discharge/charge rate systems and energy transport. Once the electrical rail machine gun is built, the per-shot costs are pretty low (copper, lead, machining) and grid supplied energy (hello supply-lines), but then a 7.62x51mm NATO round is $0.42 (in volume). The rail guns that being trialed are monsters: not a whole lot of point in shooting a $0.42 NATO round when you have nuclear power generator to recharge the gun. By the same token, there's probably not a whole lot of point spending $100k per soldier to kit them with a barely portable weapon that is matched by a $2,000 AR-15 firing $0.42 mass-produced ammunition with a mature supply line and easy portability. But, yeah, I'd like to see them, too...
- mlyle 7y ago
  Conversely, a base Tesla Model 3 puts out about 200kW sustained for longer than most machine guns fire a string; 5.56 NATO is about 1800J; a M16 fires at 13Hz; if your process is 100% efficient this is about a power demand of 24KW or about 1/8th of what the Model 3 draws from its battery pack. Incidentally, such a Tesla-machinegun would not be regulated as a firearm in many/most jurisdictions. > the per-shot costs are pretty low (copper, lead, machining) Bullets are not machined (except for exotic uses where insane accuracy is required-- 1000yd championships employing exotic chamberings and weapons, etc).

bradyd 7y ago

The Mythbusters built one of these. https://www.youtube.com/watch?v=Y3cRNEyUTF8 https://www.youtube.com/watch?v=Y3cRNEyUTF8

natmaka 7y ago

In a similar vein the H&K G11 also had ambitious objectives and was shock-full of clever ideas, however such beasts make the KISS principle (rather decisive for a weapon) difficult to follow. https://www.youtube.com/watch?v=QGKcvM2Hh4g https://www.youtube.com/watch?v=QGKcvM2Hh4g

irjustin 7y ago
Oh man, that video reminded me of Metal Storm[1], something I hadn't paid attention to since 2008. The idea seemed so cool to the college grad in me. Clearly there are problems with ammunition handling in actual battle situations and/or long term storage that probably made this a non-viable war machine similar to the G11. [1] https://en.wikipedia.org/wiki/Metal_Storm https://en.wikipedia.org/wiki/Metal_Storm

irjustin 7y ago

Love the idea from an absurdity aspect. Accuracy is very low, portability requires a vehicle, wear is quite high on the "outside" side of the channel. Feels as effective as a repeating shotgun mounted on a car.

lightedman 7y ago
"Feels as effective as a repeating shotgun mounted on a car. " Dunno, an AA-12 loaded with HE-12 explosive rounds mounted on a car or truck could be a very effective mid-range area of denial tool.
- _djo_ 7y ago
  See the PAW-20 for an example of this taken to its logical conclusion.
  - dmos62 7y ago
    Good overview of PAW-20 https://www.youtube.com/watch?v=QHbqHx3TLBE https://www.youtube.com/watch?v=QHbqHx3TLBE
    - bradknowles 7y ago
      Wow. That was a wild hour-long trip down into weird and wonderful weapons! Thank you!
Sharlin 7y ago
I wonder just how low the accuracy was (well, to be a pedant, I presume the main problem was precision rather than accuracy). The 99% use case for machine gun fire (and indeed rifle fire in modern warfare) is suppression.
KineticLensman 7y ago
"Thank the Lord / That we have got / The Gatling Gun / And they have not"

aitchnyu 7y ago

I guess the lack of rotation of the bullet made it inaccurate?

chroma 7y ago

I'm rather surprised that there isn't more innovation in firearms. For example: Has anyone tried to build a rifle that fires inert pellets using a combustion chamber powered by hydrocarbons (say… propane) and an oxidizer (oxygen or nitrous oxide)? That would make ammunition much lighter and cheaper, eliminate the need for brass feeding/extracting mechanisms, and allow for "dial a velocity" by feeding different amounts of gas into the combustion chamber. Another possibility would be to have a belt that accelerates the projectile. The "ammunition" in that case would be batteries and inert projectiles. Like a propane gun, velocity could be customized for each shot by varying the belt speed.

throwaway2048 7y ago
Part of the issue with a design like this would be that storing compressed gases is very bulky and prone to catastrophic total failure (very bad for a weapon being abused by grunts). Gunpowder in cartridges already contains an propellant and oxidizer, and per mass you really aren't going to gain anything from going with a gas based system. Heat management would also be a huge issue, spent casings carry away a surprisingly large amount of heat, and even then most guns are unable to sustain continuous fire rates for long. This was a serious issue with case-less ammunition designs for instance.
- donaltroddyn 7y ago
  Yeah, anyone who's had a brass casing land down the back of their neck can attest to how much water heat they draw away from the weapon. I also wonder how important the gas exchange caused by the mechanical cycling of the action is to cooling, as most modern rifles are pretty well sealed when in battery.
GhettoMaestro 7y ago
Some stuff gets pretty advanced. Check out the M134D. Sure it’s 1960’s tech, but it’s still amazing.
rocqua 7y ago
A nice thing about brass cases is that they also provide a really good seal around the breach. Especially because brass is flexible enough for the thoat to expand and seal against the start of the barrel. Any other gas based system needs to deal with keeping exploding gas from leaking out the holes through which you feed in new bullets.

nabla9 7y ago

DREAD from 2004 http://www.defensereview.com/world-exclusive-video-dread-weapon-system-devastating-jam-proof-and-silent/ http://www.defensereview.com/world-exclusive-video-dread-wea...

artsyca 7y ago

Centrifugal force is a fictional force it's due to centripetal acceleration https://en.m.wikipedia.org/wiki/Fictitious_force https://en.m.wikipedia.org/wiki/Fictitious_force

shalmanese 7y ago
relevant xkcd: https://xkcd.com/123/ https://xkcd.com/123/

tyingq 7y ago

2000 rounds per minute is pretty impressive. Though miniguns/Gatling do much better these days...6k/minute. And not terribly complicated in how they work. The concept fits mostly in one animation: https://qph.fs.quoracdn.net/main-qimg-e01cffa77db21231f6d9da19970d9ef3 https://qph.fs.quoracdn.net/main-qimg-e01cffa77db21231f6d9da...