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US Navy Tests Supersonic Heavy Gun Firing Magnetically-Propelled Shells @ Mach 7
Reaganite Republican ^ | March 2, 2012 | Reaganite Republican

Posted on 03/02/2012 5:28:46 AM PST by Reaganite Republican


'a game-changer'

British multinational BAE Systems has developed a functioning prototype of a new artillery piece for the US Navy's testing purposes, and what it does is propel a specially-designed shell to high supersonic velocities (cca 5600 mph) via powerful magnetic rails. At Mach 7, the projectile arrives almost three times as fast as the Navy's current big guns can deliver one, and at an astonishing range of 50-100 nautical miles (!) The new technology is now undergoing testing in Virginia.

Considering that today's naval artillery can reach only about
15 mi -and that long-range cruise missiles poke-along at a leisurely 550mph- it's easy to see how the daunting new weapon is already being called 'a game-changer'. Other uses quickly come to mind, such as the land, air, of sea based missile-defense systems for which it seems manifestly suited: paired to real-time drone/satellite intelligence and laser-guidance, there's not much a handful of these couldn't stop.

Some experts feel the new gun wouldn't even need to employ explosive shells, as a 40' chunk of metal arriving at over five thousand miles per hour should obliterate pretty much anything that happens to be sitting on Point B:


The USN has already spent seven years and $200M+ on development, with further funding still at the whim of the current US administration, be it a new Republican WH or -heaven forbid- another 4 years of steep decline under the Obammunists. 

A second variation on the theme is about to be delivered to the Navy by competing contractor General Atomics. , and while the (first) BAE gun seems to be performing well as a weapon, residual engineering challenges mostly concern building practical durability into such a mind-bogglingly powerful device... a task that is likely to take a few more years. Various cooling systems are being experimented with at this point in the development cycle, the goal being a capability of 10 rounds/min without melting the hyper-stressed barrel... at a range of up to 
200 nautical miles (!)

This of course comes at a perfect time for the US, as China seems determined to build a blue-water navy to challenge American naval supremacy, missile proliferation continues to run rampant, and the Iranian Navy -as always- could use a sinkin.

Yet hard to believe Obama hasn't tried to cancel this thing yet-
so noisy, unpleasant, polluting, and just mean... who needs that

Video/graphics/more at Reaganite Republican
_______________________________________________


British Forces News   The Telegraph   LiveLeak    Fellowship of the Minds


TOPICS: History; Military/Veterans; Politics; Science
KEYWORDS: artillery; navy; supergun; supersonic
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To: Reaganite Republican

‘The USN has already spent seven years and $200M+ on development...’

Wow, thats amazingly inexpensive as far as weapon systems go w/ this much umph. Its hard to understand why it wouldn’t continue to be funded if its meeting engineering/performance goals & expectations.


51 posted on 03/02/2012 6:59:04 AM PST by 556x45
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To: Little Ray
Coriolis effect;



52 posted on 03/02/2012 6:59:11 AM PST by FreeAtlanta (Liberty and Justice for ALL)
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To: 556x45

I wonder if another version couldn’t be made for anti-aircraft and anti-missile. Have a rod that will “shotgun” after coming out of the barrel. Get a Mach 7, 10 or 20ft pattern of BBs coming at an aircraft, missile or a speedboat.

hmmmm, add that to the defensive layer along with our missiles, Phalanx guns, and hopefully some tactical lasers.


53 posted on 03/02/2012 7:05:20 AM PST by FreeAtlanta (Liberty and Justice for ALL)
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To: theBuckwheat

“Gee Bears.” Dan Simmons, “Flashback.”


54 posted on 03/02/2012 7:11:18 AM PST by Dr. Bogus Pachysandra ( Ya can't pick up a turd by the clean end!)
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To: King Moonracer

Well - this isn’t exactly rocket science (TM ;-) This is a Magnetic Rail gun - it works on the same exact principal as a MagLev train. Just different scaling. Building a practical one is the big secret - not the physics is using.


55 posted on 03/02/2012 7:15:09 AM PST by fremont_steve
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To: skeeter

Recoil is an interesting issue. For a regular gun, it depends on the mass of both the power charge and the projectile (and sabot, etc, if present).

As a rough estimate, you can assume all that mass, including the gases resulting from the powder charge, acquires a velocity equal to the muzzle velocity of the projectile proper.

Thus, the total momentum can be approximated by the total of the above masses times the projectile velocity. This is the impulse, the ‘kick,’ that is transferred to the gun, the ship, and the ocean (according to the law of conservation of momentum).

I don’t know what the comparison of powder mass to projectile mass is for big guns, but for small ones you often find the same order of magnitude, meaning that somewhere around half the kick of a small weapon is due to the propellant gas.

If this holds true for large naval guns, then the railgun

1. Has no recoil contribution powder gases;
2. Has less recoil due to the smaller projectile (how much smaller I know not)
3. Has more recoil due the the higher ‘muzzle’ velocity.

(By the way, there are large peak forces internal to the power supply, regardless of the technology it is based on.)

I don’t know the numbers for traditional big naval guns, but let’s say the railgun projectile is, say, 100KG, which is much smaller than that of a big gun.

Taking the railgun postulated in my previous post, the peak reaction force on the railgun and the ship would be 28.8 million newtons, or around 3600 tons.

The firing will impart 2.88 million KG-M of recoil impulse, and the projectile will possess a kinetic energy of 288 megajoules.

They’d better have a good energy-absorbing mount, or the recoil from the gun will eventually tear the ship and its contents to pieces! Of course, this issue has been dealt with continually since the days of the rope-restrained cannon on wooden warships.

(Anybody have a clean napkin, check my math.)


56 posted on 03/02/2012 7:15:47 AM PST by Erasmus (BHO: New supreme leader of the rollin' homey empire.)
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To: Reaganite Republican

While rail gun is amazing and without question a game changer the 16” guns on the Iowa Class battleship have a 24 mile range not a 15.. but of course, sadly the iowa class boats are currently mothballed.


57 posted on 03/02/2012 7:17:13 AM PST by HamiltonJay
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To: FreeAtlanta

Seems like theres loads of potential. I think (not completely sure) the biggest problem is the power supply. At least in the beginning they were massive. I think they still are. For a ship thats not a problem but anything else makes it a nonstarter. The good news is theyre putting research $ into it so theres a hope for better, smaller in the future.


58 posted on 03/02/2012 7:21:15 AM PST by 556x45
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To: MichaelP

Well, since its relying on electromagnetism and not gunpowder, I suspect the kick is far less than one should suspect. At least as far as I understand the technology.

You aren’t directing an explosion, that wants to expand in all directions here out a nozzle here, you are progressively moving a projectile with magnetic force faster and faster over a short distance.

Think of it more along the lines of a SUPER roller coaster magnetic launcher, than a standard gun. Just far more powerful, and extreme.


59 posted on 03/02/2012 7:21:15 AM PST by HamiltonJay
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To: skeeter
I’d guess this system had less recoil than a conventional one.

Only if the projectile's mass was really small. The kickback force is exactly equal to the launching force, which is: F = m x a. (Force equals mass times acceleration.)

Such a gun would have a much higher recoil than convensional simply because the acceleration is high.

60 posted on 03/02/2012 7:21:50 AM PST by GingisK
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To: Drawsing
I am probably wrong, but I didn’t think rail guns had any recoil.

Yep, you are wrong. The laws of motion are not changed just because you choose a different motive force.

61 posted on 03/02/2012 7:23:14 AM PST by GingisK
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To: Erasmus

Because of the length of the weapon I guess it would be a spinal-mounted rail-gun (it wouldn’t be turreted, you would turn the whole ship to aim it).

The whole ship would basically be engineered as a single piece of ocean-going artillery to absorb the humongous recoil.

Sucks for the crew with quarters near the muzzle. Every six seconds you get woken up by a sound like Mt Pinatubo erupting.


62 posted on 03/02/2012 7:25:40 AM PST by agere_contra ("Debt is the foundation of destruction" : Sarah Palin.)
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To: FreeAtlanta
Could you imagine a version that would splinter into hundreds of thousands of shards at about a half mile above a group of ships?

Unfortunately, a shard with, say, only a KG of mass would lose much of its kinetic energy in a half mile through low altitude atmosphere. (How much is difficult to say.) You need big chunks so that the wind resistance doesn't dissipate their energy quickly.

Still, a round could be developed along the lines you propose if the lower total kinetic energy is more than offset by the area coverage. And it wouldn't necessarily have to fragment at a half mile; maybe much closer, thus losing less total kinetic energy.

And the aiming of a single, small, hypervelocity projectile at large distances (> 100 mi) is problematic, which argues further for a fragmentation round for certain target situations.

63 posted on 03/02/2012 7:28:11 AM PST by Erasmus (BHO: New supreme leader of the rollin' homey empire.)
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To: Drawsing

Newton’s law is still in effect, whether for rail or gunpowder tube. For every action, there is an equal and opposite reaction. In this case, the whole platform would absorb the energy.


64 posted on 03/02/2012 7:29:31 AM PST by lurk
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To: Yo-Yo

Not exactly; the path of the shell would be a ballistic trajectory, affected by gravity, drag, launch velocity, and launch angle, probably somewhere between 1.5 and 1.9 times the straight line distance between the launcher and the target.

Seems closer to a two-minute flight time...


65 posted on 03/02/2012 7:30:44 AM PST by bt_dooftlook (Democrats - the party of Amnesty, Abortion, and Adolescence)
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To: HamiltonJay
It doesn't matter what force it is... kinetic energy in one direction results in kinetic energy in the opposite direction!

Mike

66 posted on 03/02/2012 7:31:32 AM PST by MichaelP (The ultimate result of shielding men from the effects of folly is to fill the world with fools ~HS)
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To: 556x45
Yet hard to believe Obama hasn't tried to cancel this thing yet-

Why? When he can sell the design to our enemies and then shut down the program here. I'm not sure why he'd need the additional billions it would likely be worth, though, the rake on the current scams the administration is running should be upwards of ten billion--unless he is just an idealogue and working cheap.

67 posted on 03/02/2012 7:33:34 AM PST by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing)
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To: 6ppc

“I think he really meant 40 lb projectiles, not 40 foot projectiles. “

I think 40’ is correct. Good pics, etc., at link.


68 posted on 03/02/2012 7:36:54 AM PST by Dr. Bogus Pachysandra ( Ya can't pick up a turd by the clean end!)
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To: HamiltonJay

Ignore my roller coaster analogy, that’s a different technology... but still recoil will be far far less a standard gun would be for equivalent velocities.. of course gunpowder could never reach the full velocities of a rail gun anyway.


69 posted on 03/02/2012 7:38:08 AM PST by HamiltonJay
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To: agere_contra
Because of the length of the weapon I guess it would be a spinal-mounted rail-gun (it wouldn’t be turreted, you would turn the whole ship to aim it).

In that case, they could have a barrel much longer than 10 meters, thus diminishing the peak G's and the peak recoil force, although no decrease in the total recoil impulse.

But the gun would still need to be adjustable in elevation.

70 posted on 03/02/2012 7:38:12 AM PST by Erasmus (BHO: New supreme leader of the rollin' homey empire.)
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To: Yo-Yo

1kg to .99c takes 152 billion kilowatt-hours.


71 posted on 03/02/2012 7:42:20 AM PST by ctdonath2 ($1 meals: http://abuckaplate.blogspot.com/)
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To: Erasmus

I’ll take your word for it:)


72 posted on 03/02/2012 7:44:09 AM PST by skeeter
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To: agere_contra
Hmm an entire ship built around an insanely powerful gun... seems like I've been on this trip before...


73 posted on 03/02/2012 7:44:25 AM PST by HamiltonJay
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To: MichaelP

Mike,

The bullet in a standard gun only absorbs so much of energy of the gunpowder, You are right that for the bullet to move at a velocity of so much one direction, at least that much energy must return the other direction, but because with gunpowder, the bullet get all the energy exerted by the gunpowder, the “kick” is greater than simply the kinetic energy by some factor.

In a rail gun, you don’t have the additional forces fo the exploding gunpowder to deal with, so while its still going to have a nice kick, it should be less relatively speaking than a standard gun for equivalent performance.

of course Rail Guns vastly outperform standard guns, so the overall kick is going to be huge, but if you were to stage the rail gun to fire an equivalent projectile at standard cannon velocities its kick would be less.


74 posted on 03/02/2012 7:50:22 AM PST by HamiltonJay
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To: HamiltonJay

That should read the bullet doesn’t get all the energy from the gunpowder.


75 posted on 03/02/2012 7:52:14 AM PST by HamiltonJay
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To: ctdonath2
1kg to .99c takes 152 billion kilowatt-hours

Hmm. Seems a tad high. It'd take forever to charge the caps. How about to just .98C?

76 posted on 03/02/2012 7:53:12 AM PST by Yo-Yo (Is the /sarc tag really necessary?)
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To: Erasmus

Hmm good point about the elevation.

Unlike land-based arty, the ship is bobbing around on water. A keel-mounted weapon would have to be ‘floating’ to a certain extent to deal with roll and pitch. Mobile tank weapons obviously deal with these kinds of problems: but not artillery: and not with the added stress of a 100 or 200 nm range.

I wonder if they could micro-manage liquid ballast (or something) to give the desired slant of firing platform every six seconds.


77 posted on 03/02/2012 7:53:36 AM PST by agere_contra ("Debt is the foundation of destruction" : Sarah Palin.)
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To: Drawsing

“I am probably wrong, but I didn’t think rail guns had any recoil.”

There is recoil. Unless it has it’s own propulsion.


78 posted on 03/02/2012 8:00:01 AM PST by Slambat (The right to keep and bear arms. Anything one man can carry, drive or pull.)
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To: reg45
How do you “aim” at something that is 200 nautical miles away?Inertial nav or GPS, but the electronics would take a beating by the G forces.
79 posted on 03/02/2012 8:02:29 AM PST by cpdiii (Deckhand, Roughneck, Mud Man, Geologist, Pilot, Pharmacist. THE CONSTITUTION IS WORTH DYING FOR!)
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To: Vinnie

One of it’s original design theories was for the ability to launch from low gravity areas both cargo and space vehicles, such as, from the surface of the moon. In order to test the launch rail on earth, much more power is needed. Another spin-off of this concept is the mag-lift train in Japan.


80 posted on 03/02/2012 8:10:56 AM PST by BerryDingle (I know how to deal with communists, I still wear their scars on my back from Hollywood-Ronald Reagan)
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To: agere_contra
Sucks for the crew with quarters near the muzzle. Every six seconds you get woken up by a sound like Mt Pinatubo erupting.

I'd reckon the 'barrel' would have to be vented, otherwise the low pressure area created behind the accelerating projectile would cause problems, either with acceleration of the projectile or with air rushing back in when the projectile left. Somewhere astern of the muzzle, there'd be a 'great sucking sound'...

81 posted on 03/02/2012 8:13:03 AM PST by Smokin' Joe (How often God must weep at humans' folly. Stand fast. God knows what He is doing)
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To: Smokin' Joe

It’d be like living inside a Glock.


82 posted on 03/02/2012 8:24:49 AM PST by agere_contra ("Debt is the foundation of destruction" : Sarah Palin.)
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To: Eagle of Liberty

If you shot it up and then have if fall to earth like an icbm you would reach a terminal velocity and lose the obvious speed advantage of mach 7.


83 posted on 03/02/2012 8:28:05 AM PST by Walkingfeather
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To: 556x45
I am not a huge fan of the Transformers movies, but I liked the scene where the Navy used their secret rail gun.


84 posted on 03/02/2012 8:38:24 AM PST by FreeAtlanta (Liberty and Justice for ALL)
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To: HamiltonJay
Hmm an entire ship built around an insanely powerful gun... seems like I've been on this trip before...


:-)

85 posted on 03/02/2012 8:46:24 AM PST by FreeAtlanta (Liberty and Justice for ALL)
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To: HamiltonJay

86 posted on 03/02/2012 8:47:28 AM PST by FreeAtlanta (Liberty and Justice for ALL)
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To: fremont_steve
USN has already spent seven years and $200M+

Well, rocket science or not, every dime the Chicomms save on their development by stealing ours is another bullet for their rifles. The nuclear and missile secrets pissed away by the Klintoons saved them billions. IP is a competitive advantage.

87 posted on 03/02/2012 9:41:59 AM PST by King Moonracer (Bad lighting and cheap fabric, that's how you sell clothing.....)
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To: Yo-Yo; Calvin Locke

The projectile would almost certainly be laser or GPS guided with pop out fins like current smart weapons, or something that would be viable at Mach 7, anyway

They couldn’t possibly be planning to send these things dumb and blind, I can’t fathom it


88 posted on 03/02/2012 10:08:35 AM PST by Reaganite Republican
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To: Walkingfeather

horizon is about 16nm at sea - as someone else noted the old battleships pinged shells downfield to 23nm. There are any number of issues that would have to be addressed in targeting (beyond the target itself) which the navy has been doing for years - weather, coreolis effect (earth’s rotation under the trajectory), spin of the shell.

Targeting would most likely be linked down from satellite or aircraft at altitude (other ships or helos that are over the horizon and closer to the target, but why risk it). At the rate of fire they mentioned and the potential kinetic energy you get 2-3 in the vicinity in a minute, minor correct 2-3 on target and move on to the next...could wipe a fleet in half an hour tops with one asset and no radiation.

Also being on a moving platform if the bombers aren’t airborne trying to eliminate the source would required very long range patrols or satellite tech to find, avoid, and destroy. If they are airborne then would lose at least a few high value assets prior to redirect.

I’m thinking long term the boomers (ballistic subs) get fitted with one of these - get their target orders, surface, open the can, fire, close the can, submerge until new target orders received....as an ex-surface guy I just messed myself a little with that scenario.


89 posted on 03/02/2012 10:11:19 AM PST by reed13k (For evil to triumph it is only necessary for good men to do nothing.)
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To: GingisK

I would think the force is spread out over time more evenly than the more instaneous/reaction of an explosion, no?

Same reason an electric tram or streetcar will jerk you off your feet if it takes off too suddenly, yet still only reaches the same ultimate speed as if it had accelerated more evenly and smoothly... as perhaps this weapon is doing, building momentum in a linear fashion, not just one big KA-BOOM as one would have with a conventional explosive propellant

jmho


90 posted on 03/02/2012 10:12:58 AM PST by Reaganite Republican
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To: GingisK; All

I would think the force is spread out over time more evenly than the relatively instaneous/reaction of an explosion, no?

Same reason an electric tram or streetcar will jerk you off your feet if it takes off too suddenly, yet still only reaches the same ultimate speed as if it had accelerated more evenly and smoothly... as perhaps this weapon is doing, building momentum in a linear fashion, not just one big KA-BOOM as one would have with a conventional explosive propellant

jmho


91 posted on 03/02/2012 10:14:01 AM PST by Reaganite Republican
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To: Reaganite Republican
Given the muzzle velocity of Mach 7, the acceleration is enough to simulate a KA-BOOM.
92 posted on 03/02/2012 10:46:04 AM PST by Yo-Yo (Is the /sarc tag really necessary?)
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To: Reaganite Republican
I would think the force is spread out over time more evenly than the more instaneous/reaction of an explosion, no?

Mach 7 in what distance? The recoil will be significant because the gun is not really that long. Remember, 16-ich guns on battleships were long, but recoiled smartly nevertheless.

93 posted on 03/02/2012 11:21:52 AM PST by GingisK
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To: agere_contra

Big naval guns have been known to have a mechanism that fires them in sync with the ship’s instantaneous pitch; that is, at the instant that the pitch gives the angle of the barrel for which the firing solution was calculated.

With a railgun, you may even be able to near-instantaneously choose the amount of impulse to be given the projectile, thus fine-tuning the firing solution.


94 posted on 03/02/2012 12:03:08 PM PST by Erasmus (BHO: New supreme leader of the rollin' homey empire.)
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To: ctdonath2
And if the projectile had a time fuze, it would get really confused. You'd have to set it for something like a millisecond, and then hope to God that it would actually get up to the rated speed.

≤}B^)

95 posted on 03/02/2012 12:09:20 PM PST by Erasmus (BHO: New supreme leader of the rollin' homey empire.)
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To: Tallguy; MichaelP
"It must create one hell of a kick too!...Should be able to calculate it. We know the muzzle velocity and can make an estimate as to the barrel length."

From what I understand, I don't think those conventional formulae would apply here, although in fact, Newton's Third Law still applies.

In a typical firearm, the combustion of the powder is channeled to propel a bullet down a strictly defined path (i.e., the barrel). There is an "equal and opposite" reaction in which the rifle moves with equal force against the shooter's shoulder.

As I understand it the rail gun is more akin to a slingshot where the launching of the projectile is actually the "reaction." In a slingshot, the "action" occurs when energy is expended to draw the elastic. That energy is stored until released at which time the "reaction" propels the projectile forward. Similarly, a rail gun stores up electromagnetic energy, which is released in the launch of the projectile.

That's the way I understand it, but if I'm wrong, I'm sure there will be numerous others here who will correct me :-)

96 posted on 03/02/2012 12:48:36 PM PST by Joe 6-pack (Que me amat, amet et canem meum)
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To: Reaganite Republican

The Chinese will have this technology before Obammy leaves the office.


97 posted on 03/02/2012 8:14:51 PM PST by ExpatGator (I hate Illinois Nazis!)
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To: GingisK

Good question

It is striking the seeming lack of recoil in the video, tho... maybe the thing is bolted down into a mile of bedrock


98 posted on 03/03/2012 12:13:38 AM PST by Reaganite Republican
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To: Joe 6-pack
From what I understand, I don't think those conventional formulae would apply here, although in fact, Newton's Third Law still applies.

Those formulas do indeed apply here, as they are all related to the Newtonian Principles. Assume that the railgun has mass of its own and is well anchored.

Even electric motors have kickback. Try this for yourself: Get a small toy DC motor, and connect it to two leads. Lay the motor on a table so that it is free to move. Touch the wires to a battery, and observe that the motor jumps on the table as its housing rotates in the opposite direction to the shaft. That is evidence of a counterforce to the magnetic force that moves the armature. The railgun is a linear electric motor, and follows the same rules.

99 posted on 03/03/2012 8:39:50 AM PST by GingisK
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To: HamiltonJay
the bullet get all the energy exerted by the gunpowder, the “kick” is greater than simply the kinetic energy by some factor.

That is not strictly true. The bullet is accelerated by the pressure according to the formula F = ma, a = F/m. It reaches a final velocity proportional to the length of the barrel and the force exerted by the pressure. The pressure is not steady throughout the acceleration because the powder does not burn all at once and the volume of the hot gas increases as the bullet travels down the barrel exposing more bore space to the hot gasses. (Calculus must be used because the pressure and volumes are not constant.) The bullet is fully accelerated as it leaves the barrel, and its momentum is expressed as "M = mv". The rifle experiences the exact same momentum in the opposite direction, however it is more massive than the bullet. The rifle and its operator do not achieve anywhere near the same velocity just because of their higher mass. There is a bit more momentum imparted to the rifle as the high pressure gas is vented out the muzzel.

100 posted on 03/03/2012 8:59:20 AM PST by GingisK
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