DREAD weapon system, power requirements

[extreme_machinations]

HOW 'S THIS DREAD SYSTEM DIFFERERNT FROM A BASEBALL OR TENNIS BALL MACHINE[THE ONE THAT THROWS BALLS AT YOU] ,i bet the inventor got the idea from these ,just changed the balls to golf balls ,hehehehehehehehehehehe
STUPID GIT probably could'nt work out the momentum details .

 

[Danger]

HOW 'S THIS DREAD SYSTEM DIFFERERNT FROM A BASEBALL OR TENNIS BALL MACHINE

As far as I know, all pitching machines use the same system as the Hot Wheels 'supercharger' I had 40 years ago. ie: the ball (or car) is introduced to the rim of a rapidly spinning wheel(s), and almost instantly accelerated to it's launch velocity. This Dread fiasco seems to maintain them in a constant state of acceleration which is confined by the housing until the release mechanism (and how the hell does that work?) unlocks and let's them out.

 

[extreme_machinations]

i think even in a pitching machine the ball is introduced at the centre of the spinning wheel fitted with throwing arms which is then acclerated[rotated] ,the ball then slides up the throwing arms and flies off tangentially at the realease point which is same as the dread sys ,a slight diff is that it just doesn't hold the balls long enough for the machine to accelerate it to a high speed .
yup ,to me they're both same .

 

[Danger]

i think even in a pitching machine the ball is introduced at the centre of the spinning wheel fitted with throwing arms which is then acclerated[rotated

That might be right. I've only seen them from a distance or on TV. Regardless, no one ever claimed that they have no recoil. They also have a barrel of sorts for accuracy.

 

[lynxpilot]

My approach would be to try to 1. not put the cart in front of the horse, and 2. not to reinvent the wheel.

There were some claims by the inventor and the supporters of the inventor that the weapon has "no recoil", emphasis on quotes. I will quote more loosely the other claims because I can't be bothered to look them up and that would be the 8,000 fps projectile velocity, with 120,000 rounds per minute, and a 150 W power supply.

All you need to do is to take the weight of the projectiles, the velocity, the firing rate, and to calculate the power requirement. Use physical constants like conservation of energy and momentum. Take the energy of each projectile divided by the rate of fire and come up with power. It's easy. You can also calculate the force on the weapon which will create recoil. And of course you, as physics students, know that this weapon cannot fire projectiles of ANY mass without recoil. That alone is enought to debunk the whole thing.

This thing is a hoax. Use your basic skills in physics.

 

[JO 753]

I woudnt be so quick to dismiss this, especially since they are claiming a working prototype. I can think of several things rite off the top of my head to counter some of the major problems you are citing. Going by the patent info is useless, since it could be purposely misleading to keep the device from being copied. Same thing could apply to some of the obviously wild claims.

 

[Danger]

Going by the patent info is useless, since it could be purposely misleading to keep the device from being copied.

Not if it's obtained from the Patent Office.

 

[pervect]

I woudnt be so quick to dismiss this,

I guess there's one born every minute, as PT Barnum said.

 

[JO 753]

Maybe you have yet to discover the value of patent 'protection', Danger. The only real way to protect an idea is to keep it out of the heads of anybody who may want to steal it.

 

[Danger]

Maybe you have yet to discover the value of patent 'protection', Danger.

I have a pretty fair exposure to patents, actually. Information obtained from a Patent Office is a copy of the original filing. No one knowingly files false information in a patent application for a practical product, because it doesn't protect the real design. The patent is for legal purposes only, giving you the right to seek compensation through the courts if someone kifes your idea. A false filing would do nothing in that regard, and anyone can still 'reverse engineer' the thing once they see it.

 

[agribusinessman]

1. Velocity 800 ms ~ approximation from literature
2. Diameter 762 mm – assumed from “32 inches wide” in literature
2. Rotational Speed ~ 20051 RPM (335 Hertz) - derived from diameter assumption.
3. Feeder Trays - 20 (from literature).
4. Mass of projectile: 4.633 g - Huh? I would use 3.7 grams. You don't know the exact alloy so the density is +/- 1 percent. A stainless steel dimpled ball of 7.62mm (.308) diameter is 1.7 grams, 12.7 mm (50 caliber) is 8.3 grams (1-2% loss due to dimpling) . Density is 18.8 for tungsten, 15.7 g/cm3 for tungsten carbide, and 8.0 for stainless steel. The steel ball weights are for actual steel balls (commercially available) derated 1% for dimpling.
5. Shot burst: 10. This causes some conflict with the 120000 rounds per minute number since it implies a rotation speed of 12000 rpm (200 hertz). Which implies the production device will be 1.3 meters wide (allowing for outer casing width).

From the above:
1. The device fires 10 rounds per spin (1/2 of trays). As long as the device is programmed to fire in units of 10 it will only experience rotational torques for a fraction (9/10th) of a rotation and will be balanced when not firing.
2. The device fires in a 2 cycle round robin. This gives the 3 ball shot advance mechanism 2 cycles to move the next ball in a set of trays into position.
3. The device operates at the speed of a high performance hard drive (which takes 7 watts and can spin up in several seconds).
4. There is talk of "reloading/rearming" in the patent. Although a gatling gun loading mechanism is possible (dump shot into the center of the disk and let rotational inertia fill the slots) reloading and firing are apparently separate steps.
5. I am familiar with mechanical harvesters (for tree crops) which use 30 hertz rotations, and 100 lb edge weights on 2 ft reaction wheels. The rotational speed of the harvester is 1/10 that of the Dread device resulting in accelerations 1/100 as great on an weight imbalance 10000 times greater. The havester is not destroyed by use. Pneumatic isolation of the disc (perhaps with fluid dampening) will be sufficient to deal with the momentary imbalances. The motor should be connected to the wheel with a flexible coupling.
6. If the weight imbalance acts through the center of mass on the axis the net effect of the forces won't cause precession, i.e. the forces won't have a component perpendicular to the plane of rotation.
7. Start up torque requirement. For the sake of argument we will assume that the weight of the ammunition (308 caliber) is 3700 grams. The weight of the “disk” is assumed to be the same as that of the ammunition. Total weight 7.4 Kg. Radius = .76 m. Moment of inertia ~ 2.14 kg/m2 (solid cylinder approximation). 5 second start up is assumed (same as a computer hard drive).
a = Δv/Δt
acceleration = 2* Π * 335 hertz/5 = 210 rad/s2
t = Ia = 2.14 kg*m2 * 210 /s2 = 449 kg * m2 /s2 = 449 Nm

449 NM is a fairly large electric motor (on par with an engine dynamo). So the system is practical but has a fairly long “arming” period (longer than the 5 seconds used for illustration) for the disk to spin up prior to firing. There will be a loss of rotational speed during continuous fire. Making the inertia of the disk greater will mitigate this.

 

[pervect]

1. Velocity 800 ms ~ approximation from literature
2. Diameter 762 mm – assumed from “32 inches wide” in literature
2. Rotational Speed ~ 20051 RPM (335 Hertz) - derived from diameter assumption.

While you're at it:

centripetal acceleration of disk:

(800 m/s)^2 / .4 m = 1,600,000 m/s^2

(I used 400 mm for the radius, that's rounded up, and closer to 16" than your figure).

For comparison, a typical high speed centrifuge generates "up to 30,000 gravities" (from the www - that's only 300,000 m/s^2), and it has only a static load, not the dynamic load generated by feeding it bullets.

I think if you look back in the thread you'll see calculations that the 800 m/s version will fragment a steel rotor even without any other loads.

 

[SK]

1. Velocity 800 ms ~ approximation from literature
2. Diameter 762 mm – assumed from “32 inches wide” in literature
2. Rotational Speed ~ 20051 RPM (335 Hertz) - derived from diameter assumption.
3. Feeder Trays - 20 (from literature).
4. Mass of projectile: 4.633 g - Huh? I would use 3.7 grams. You don't know the exact alloy so the density is +/- 1 percent. A stainless steel dimpled ball of 7.62mm (.308) diameter is 1.7 grams, 12.7 mm (50 caliber) is 8.3 grams (1-2% loss due to dimpling) . Density is 18.8 for tungsten, 15.7 g/cm3 for tungsten carbide, and 8.0 for stainless steel. The steel ball weights are for actual steel balls (commercially available) derated 1% for dimpling.

These are values I approximated by looking at the patent paper, the DefRev article and by using common values in current weapon tech (bullet speed and diameter) for comparison. I set density of Tungsten to 20 g/ccm, that´s not too far from 19.3g/ccm you commonly find.

3. The device operates at the speed of a high performance hard drive (which takes 7 watts and can spin up in several seconds).

Well a hard drive doesn´t spin that fast (yet), and it´s a closed, light system, so the comparison doesn´t tell much.

I am familiar with mechanical harvesters (for tree crops) which use 30 hertz rotations, and 100 lb edge weights on 2 ft reaction wheels.

Do you got a picture of these? Isn´t there a counterweight so net centrifugal forces amount to zero?

6. If the weight imbalance acts through the center of mass on the axis the net effect of the forces won't cause precession, i.e. the forces won't have a component perpendicular to the plane of rotation.

Well, the thing will still react wildy to changes in direction due to gyroscopic effect. I think that was the main issue presented here.

449 NM is a fairly large electric motor (on par with an engine dynamo). So the system is practical but has a fairly long “arming” period (longer than the 5 seconds used for illustration) for the disk to spin up prior to firing. There will be a loss of rotational speed during continuous fire. Making the inertia of the disk greater will mitigate this.

449NM might doesn´t seem much, but 449NM at 20000 RPM isn´t quite as easy to achieve, IMHO something like this will badly get into the way:

No matter what the torque requirements are, the power requirements I calculated are valid and in the Megawatt range. It might be possible to make the problem sound small by presenting a value like 449NM, but that doesn´t mean you don´t have to put an average of 0.98 MW into the system in my intial example.
Making the inertia of the disk greater might help mitigating the velocity loss of the ammo, but it also means you have to put much more energy into accelerating the whole thing, see my 20kg and 200kg disk examples above.
As Pervect said, just playing around with disk mass isn´t that trivial either, as strain on material is very high, making it a whole topic for itself.

 

[Felix_the_cat]

Almost no recoil

Hey guys,
here comes the next foreigner with bad english.
I'm from Germany

I read your whole discussion, and if you consider the projectile which is shot, is not replaced by another one, there will definitely be a recoil.

But, just imagine two rails spinning round the center of a closed circled box. (check attachments)

If you then put a ball in the middle, it will be draged out as far as possible.

If you now put in 20 on each rail and one ball is released from one of the two rails another ball wil replace it at once.

The difference of weight on the one rail will be almost in the center of mass, and if balls a continously supplied eliminated at once.

 

[3trQN]

It claims to be virtually silent haha, when was the last time you heard (sorry didnt hear) an electrically powered centrifuge that runs at 120,000rpm... This review SoldierTech reads like some trekky has had too much coffee when writing the review...

It may be virtually silent when running in your head.

 

[Crosson]

To the original poster, yes you are absolutely correct. This is the true content of the equivalence principle, that a freefalling observer is in a locally flat spacetime, just like an observer moving at constant velocity. In freefall we do not feel our own weight, this is what is meant by weightlessness i.e. the lack if a force.

 

[DuckPhup]

Recoil? Nonsense! Precession? Nonsense!

A counter-rotating disk of equivalent mass will eliminate precessional effects. Not an issue.

Once the gizmo is up to speed, with fully loaded ammo channels, you've essentially got a flywheel... which wants to stay in motion (according to Newton). The only subsequent energy requirements will be what is required to restore angular momentum lost to frictional forces, and the minimal inertial forces involved in accelerating individual pellets in 1/50th-D. step increments.

Re recoil: When a pellet is released, there will be no recoil. Think about it... a bit of the mass of the flywheel will be lost. Under constant power input, the darn thing would be trying to speed up... not slow down. Of course, a velocity servo control system would tightly control that.

Unbalancing: Not an issue. Remember, the thing has a magazine capacity of 10,000 (.50 cal) or 50,000 (.308 cal) rounds. Suppose that there are around 1,000 pellets (.308) in the flywheel channels (20 x 50). That tells us that there is a central hopper full of pellets, supplying a chamber where there are a whole bunch of pellets, whirling around, desperately trying to get into the feed channels... but being prevented from doing so by virtue of the fact that the feed channels are already full. When a pellet is released, the pellet column instantly advances .308 inches, and the expended pellet is instantly replaced... the channels essentially remain solid. Any purturbance in the system created by the 'release' (NOT 'discharge') of a pellet... a very tiny fraction of the mass of the flywheel system... will be very minute, and very short-lived. So, there might be a tiny bit of vibration, which can be dampened by a sufficiently robust support/drive system. (This is probably the reason that there are 20 channels, rather than 6 or 10 or 12... or 24 or 36. Too few channels... to much vibration. Too many channels, too much additional flywheel bulk required to maintain integrity.)

Re recoil (again)... and conservation of energy: The 'recoil' is pre-loaded into the system, and is felt long BEFORE a pellet is expelled. The energy expended in bringing the flywheel (including its full load of pellets) up to its designated rotational speed is the equivalent of the 'recoil' experienced by conventional munitions.

Re Spinning projectiles: Get a golf ball, and drill a hole through it. Attach about 3-feet of kite string. Twirl it around your head, as fast as you can, then let go of the string. Does it spin? (Hint: No.)

It seems to me that such a system will operate pretty much as claimed by the inventor, and the only real impediments would be materials-related... i.e., building it from something that won't come totally unglued at the desired angular velocities. Also, diven the spherical projectiles, it probably only sufficiently accurate over relatively short ranges, compared to conventional munitions. Of course, the sheer volume of fire might mitigate that deficiency, to an extent.

 

[Mech_Engineer]

Your examples are ill-conceived at best, and misinformation at worst. Several people have gone through intensive calculations analyzing the power requirements and physics involved. Unless you have some ACTUAL MATH to prove you point, your claims are no better than the mud-slinging inventor's.

 

[WellDuh]

Easy Peasy mate

Took me maybe 10 minutes figure this one in the rough.

counter-rotating room-temp superconductor electromagnetic centrifuges with center feeds.
https://www.physicsforums.com/images/smilies/cool.gif


This balances effects of lost angular momentum by paired synchronized fire from centrifuges with opposite spin. No mechanical rotor.
https://www.physicsforums.com/images/smilies/love.gif
:!)

Bullets are magnetically levitated so as not to touch the interior once feed in - so frictionless. Magnetic gating of projectiles. Gee doesn't this sound like a pair of Cyclotrons scaled up to macroscopic particles via the miracle of superconductors?

No moving parts past the feed mechanism...and probably not there if you are clever (magnetically siphon out ammo from ammo tank).

Power arguments? Really moot. It is common for weapons to quote fire rates that cannot be sustained. So yes you are limited to the energy available during a given firing period. https://www.physicsforums.com/images/smilies/rolleyes.gif


But then again lasers commonly store up energy in capacitor banks for discharge over a short period of time. So DREAD can meet its specifications for short burst fire. Very short bursts with long recharge times for man portable. Several or longer bursts with HUMVEEs helicopters etc with short recharge periods.
https://www.physicsforums.com/images/smilies/blushing.gif


Of course several other weapon systems have started needing higher energy power plants with HUMVEEs. Not that I am endorsing them as practical or wise for the battlefield -- but reports exist of multi-megawatt power sources to accompany HUMVEE and small truck lasers coupled with large quick discharge power banks. Hmmm I wonder what a stray penetrating round would do there? Similarly what happens if those superconductors in the weapon breakdown? I am betting you don't want to be the gunner in a HUMVEE or man portable -- crispy critter time.
https://www.physicsforums.com/images/smilies/surprised.gif


Accuracy...hmmm. Well further electro mechanical gyroscopic gun stabilization would likely help (sort of like Abrams) sink minor vibrations. Plus nothing says you can't add a follow on magnetic guass gun barrel to correct aim point velocity after the ammo is "charged" with KE directed in approximately the right direction.
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Plus the anti-tank guys are missing the fact that the decreased spacing of arriving ammo is even like hydraulic drilling to armor. This gun can just afford to paint more square inches of armor with effect. Effectively the same weight of ammo is delivered per square inch even spread out a bit. That is IF there is increased drift over more stable guns, it is countered more total arriving ammo. And I am not really sure we have reason to believe there there will be more drift over something like the A10 30mm gun - after all that vibrates the whole plane in space. You need a real weapons tests or full engineering data and simulation to even speculate on this.
https://www.physicsforums.com/images/smilies/redface.gif

 

[WellDuh]

It claims to be virtually silent haha, when was the last time you heard (sorry didnt hear) an electrically powered centrifuge that runs at 120,000rpm... This review SoldierTech reads like some trekky has had too much coffee when writing the review...

It may be virtually silent when running in your head.

But what if the bullets are spun by a pair of counter-rotating superconductor electromagnets? https://www.physicsforums.com/images/smilies/love.gif
:!)
Then the only moving part is the bullets. And I suspect the chamber quickly becomes a vacuum during fire. Basically this is a Guass gun circularized to solve the recoil and barrel length problems.
https://www.physicsforums.com/images/smilies/biggrin.gif


However, the gun could still be located by stereoscopic acoustic analysis of the sonic cracks. Easily performed by a PDA and a couple of sound guns at known baseline locations a few hundred meters apart -- or militarily a radio linked system of two or more GPS locatable mobile parabolic dishes.

The real point being that an unaided human spotter couldn't locate such a superconductor gun. I forget the precise length of the base line for triangulation required. Something like it has to be longer than a halfwave length of the shockwave at the speed of sound at the observation points.

 

[WellDuh]

Your examples are ill-conceived at best, and misinformation at worst. Several people have gone through intensive calculations analyzing the power requirements and physics involved. Unless you have some ACTUAL MATH to prove you point, your claims are no better than the mud-slinging inventor's.

Weapons almost never sustain peak fire rates. Most mechanical weapons systems must stop after a few hundred rounds at peak rates due to heating effects - anything from thermal expansion effects to incipient barrel damage (phase changes in metals). Think firing in bursts.

Here the limit is likely energy drawn from a storage bank and the recharge rate of the generating power source. Oh and you can probably "pre-charge" a number of bullets in the centrifuge itself at just below release speed. Plus if needed you might be able to plug in a second or third HUMVEEs generating system to your storage (capacitor?) bank -- especially useful as not all HUMVEEs would mount such weapons.

Also remember two things. Those bursts allow you to beat through armor or break an enemy charge. And if you need sustained fire on this weapon you can drop back to as low a rate as your power source can sustain.

 

[WellDuh]

1. Velocity 800 ms ~ approximation from literature
2. Diameter 762 mm – assumed from “32 inches wide” in literature
2. Rotational Speed ~ 20051 RPM (335 Hertz) - derived from diameter assumption.

While you're at it:

centripetal acceleration of disk:

(800 m/s)^2 / .4 m = 1,600,000 m/s^2

(I used 400 mm for the radius, that's rounded up, and closer to 16" than your figure).

For comparison, a typical high speed centrifuge generates "up to 30,000 gravities" (from the www - that's only 300,000 m/s^2), and it has only a static load, not the dynamic load generated by feeding it bullets.

I think if you look back in the thread you'll see calculations that the 800 m/s version will fragment a steel rotor even without any other loads.

And there is your problem -- you assume a mechanical rotor. Is there a rotor in a Cyclotron? Nope.

So what if you applied some room-temperature superconductors to levitate and spin only the bullets themselves?

 

[Danger]

So what if you applied some room-temperature superconductors to levitate and spin only the bullets themselves?

If you can find any, I want to buy one.

 

[WellDuh]

My approach would be to try to 1. not put the cart in front of the horse, and 2. not to reinvent the wheel.

There were some claims by the inventor and the supporters of the inventor that the weapon has "no recoil", emphasis on quotes. I will quote more loosely the other claims because I can't be bothered to look them up and that would be the 8,000 fps projectile velocity, with 120,000 rounds per minute, and a 150 W power supply.

All you need to do is to take the weight of the projectiles, the velocity, the firing rate, and to calculate the power requirement. Use physical constants like conservation of energy and momentum. Take the energy of each projectile divided by the rate of fire and come up with power. It's easy. You can also calculate the force on the weapon which will create recoil. And of course you, as physics students, know that this weapon cannot fire projectiles of ANY mass without recoil. That alone is enought to debunk the whole thing.

This thing is a hoax. Use your basic skills in physics.

Recoil is a tricky question in that they are obviously talking subjective recoil. Further for physics we are asking a question of momentum and not kinetic energy.

So given two counter-rotating centrifuge systems which release projectiles with opposite momentum essentially in synchronization --what is the net effect? Total system momentum is still in balance for each pair, is it not?
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Duh 120k rounds per minute is a burst RATE. It does not say that burst rate can be sustained for a minute. In fact there are references that say a burst is like 10 rounds (or 1/200 of a second). Quoting fire rates to round per minute is merely for convenience in comparing different weapons systems.
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I suspect the time between bursts varies with what is providing main power -- obvious quite different for man carried or HUMVEE or Jet engined vehicle. And sustained fire rate is going to be much lower for all but the largest powered vehicles. https://www.physicsforums.com/images/smilies/frown.gif


Hmmm...many devices have more than one power supply. I would suspect that the quoted 150W power supply primarily refers to powering the common control mechanisms. They did say the info given was incomplete.

 

[russ_watters]

If you can find any, I want to buy one.

You can buy it - what I want is the patent!

 

[WellDuh]

While we´re at it: During the development of guns ball shaped ammunition was abandoned more then a hundred years ago. With advertising it as accurate ammo Mr. St George is a bit late.

You probably need to readdress whether the old reasons for cylindrical ammo over ball ammo is still valid.

(1) Primary reason -- Cylindrical ammo gave a much better gas seal than spherical but irrelevant in this case

(2) The aerodynamic lift effects of spinning cylinder is more easily fixed than sphere spinning in random direction -- relevant for subsonic although spherical ammo doesn't bleed energy like tumbling cylindrical ammo; But I highly suspect this is not relevant for supersonic spherical ammo as the shockwave in front of the sphere will bury rotational effects.

Also dimpling addresses many of the subsonic issues.

"St George says the projectiles travel at around 300 metres per second upon release from the weapon, about the same speed as a handgun round."...

Does anyone have the formula for velocity drop of subsonic spherical projectiles in air?

Maybe the prototype does only fire at 300 m/s. Whatever makes you feel good about your old blackpowder guns. https://www.physicsforums.com/images/smilies/biggrin.gif


However, if DREAD really does use superconductors to speed bullets similar to how a Cyclotron speeds atomic sized particles...then supersonics is easily in range given enough impulse power (as in capacitor high rate flash discharge).

I don't believe the unmodified Stokes Law applies to supersonic objects. But the rate of velocity loss is probably similar for any two simple objects presenting the same frontal surface area and without any designed supersonic aerodynamics such as wasp waisting. That would be an advantage for conventional projectiles - they can be designed to have supersonic aerodynamics for a price and at risk of complicating and jamming ammo feeds. However I've vaguely recall that once you breach the hypersonic range most of those supersonic aerodynamics once more go out of play. So unless someone can enlighten us with some links to equations --

I suspect that spherical and cylindrical ammo are just about equal in performance near and above the speed of sound. Further for anti-tank/anti-missile uses you are really at the limit of your range once your ammo drops below sonic. https://www.physicsforums.com/images/smilies/rolleyes.gif


So cylindrical ammo has a measurable range advantage for anti-personal work and unarmored vehicles once at subsonic speeds. On the other hand if the ammo starts as supersonic you are likely talking miles of range...which might mean extra range is a disadvantage because you can't see exactly who you are hitting (civilians or allies trying to flank the enemy). https://www.physicsforums.com/images/smilies/eek.gif

 

[WellDuh]

Room Temperature - maybe maybe not

If you can find any, I want to buy one.

Can you afford military prices?

Well actually technically high temperature superconductors are what is known proven state of the art. And they would be usable with a good liquid nitrogen supply.

On the other hand you did notice this might be a Bell labs guy didn't you?

 

[WellDuh]

Practical Superconductors 101

You can buy it - what I want is the patent!

Well do you think it is practical with Type IIs?

Feed me some detailed knowledge on something I am not that familiar with.

 

[WellDuh]

Practical Superconductors 101

You can buy it - what I want is the patent!

Well do you think it is practical with Type IIs?

Feed me some detailed knowledge on something I am not that familiar with.

Really I would think price would be what would make this a weapon of the distant future (20+ years).

 

[Danger]

Will somebody please lock this thread before my head explodes?
Or, at least, teach Duh how to either use smileys properly or not at all.

 

[Battleaxe12]

I agree, there has to be a recoil, if something shoots out the front, and nothing shoots out the back, conservation of momentum demands that there be a recoil.

I am studying physics in school, and I think that you are forgetting centripetal force, the reaction force happens before the projectile leaves the weapon. That force is the projectile pulling out away from the center of the centrifuge and when the projectile leaves the weapon the force goes with it. Have you ever spun around with a heavy object? the object pulls on your arms and if you release it it goes flying without pushing you back. But that doesn't mean that I believe that the weapon works as they say or even works at all there are many things that make me say it wouldn't work.

 

[Battleaxe12]

I never even thought about a superconductor but that is about the only way the claims of the manufacturer can be true, but then you would not be able to use tungsten ammo and air resistance might melt the bullets.

 

[Battleaxe12]

In WWII the air force (I can't remember whether British or American) needed bombs to destroy dams, so they decided on giant ball bombs spun to give backspin to keep them up next to the dam. Anyway they did tests and found that a dimpled ball flew further with more accuracy than a smooth ball.

 

[bassplayer142]

It is sad that the beauty of physics is clouded by advanced weaponry and destruction.

 

[farfallen]

I know i may be poking a dead post here, but i just saw the dread weapons system video on military.com, googled it, and found your forum. After reading some of the posts, I had some thoughts; firts, the 'no-recoil' thing, best guess? industry standard double speak. It is true, Newtonian physics and all that, but it is also true that given an electric propulsion coupled with proper mounting that this 'gun' would have a negligable amount of recoil; frictionless? doubtful given the rate of fire, but since the F117 can mask its thermal signature, i don't see why a gun can't; soundless? again highly doubtful, the rate of fire alone would produce *some* sort of sound, and unless theyre usingsubsonic munitions, there would be the breaking of the sound barrier, yet if they really are using subsonic munitions, then they have already defeated the purpose of the weapon. given that the spead of sound is 1125 ft/s and given that a projectile has a good chance to break skin (though not puncture) at around 200 ft/s, i suppose it's possible, but if the target were waering clothes, then the velocity of the projectile would need to be doubled; and forget about anything considered a 'soft' target ie-car door, house wall, person in body armor. This coupled with the shape of the projectiles tells me that all they have right now is a rapid fire BB gun; oh that and in the video they demonstrated their prototype against drywall