Railguns: The Fast, the Furious—and the Future?

[rangerrebew]

Railguns: The Fast, the Furious—and the Future?
January 13, 2017 | Fritz Lodge
Photo: General Atomics
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With electromagnetic railgun systems (EMRS), “faster than a speeding bullet” takes on new meaning. The 32-megajoule – a measurement of power applied over a period of time, in this case equivalent to about nine kilowatt-hours – railgun in its second phase of testing by the Office of Naval Research (ONR) can fire a projectile at seven times the speed of sound (Mach 7), almost three times faster than an M16 rifle bullet. What’s more, the weapon achieves this blistering speed without the need for volatile, expensive, and heavy chemical propellants like gunpowder.

This technology has attracted U.S. military planners’ interest. ONR tests of the 32-megajoule railgun at the Naval Surface Warfare Center Dahlgren Site in Virginia are aimed at eventual deployment of the weapon on new vessels like the Zumwalt-class destroyer, which produces the energy necessary to power the weapon.

However, bringing this weapon of the future to the battlefield is not easy, and early hopes that the railgun could enter service by the end of this year now seem far-fetched. Given the progress made and the challenges ahead, what does the future hold for the military’s super gun?

https://www.thecipherbrief.com/article/north-america/railguns-fast-furious-and-future-1091?utm_source=Aggregators&utm_campaign=804a6fdadc-EMAIL_CAMPAIGN_2017_01_13&utm_medium=email&utm_term=0_b02a5f1344-804a6fdadc-122460921

[thackney]

a measurement of power applied over a period of time

Also known as "energy".

[240B]

The 'Stargate' series had railguns on their spacecraft.


Imagine that. Railguns in space with no friction and limited gravity. That would actually be a very lethal weapon.
It is hard to even think about.

[thackney]

The 'Stargate' series had railguns on their spacecraft.


Imagine that. Railguns in space with no friction and limited gravity. That would actually be a very lethal weapon.
It is hard to even think about.

It is a very lethal weapon on earth.  "No friction and limited gravity" affects range, not the energy from the initial shot.

[240B]

It is a very lethal weapon on earth.  "No friction and limited gravity" affects range, not the energy from the initial shot.

On Earth we have to deal with pesky things like gravity, air resistance, and wind.
I kind of understand what you mean, but a railgun in space would kick the ass of a railgun on a warship.
The dynamics would be completely different.

[thackney]

On Earth we have to deal with pesky things like gravity, air resistance, and wind.
I kind of understand what you mean, but a railgun in space would kick the ass of a railgun on a warship.
The dynamics would be completely different.

Same muzzle energy for the same build.  The lack of air and the gravity are going to impact the effective range.

[240B]

Same muzzle energy for the same build.  The lack of air and the gravity are going to impact the effective range.

This is a sort of silly discussion for geeks. But it is a silly day so, why not.


I get what you mean, but the effective destructive power and any distance will be increased in space.
But there has to be a measurable loss of projectile force, just in the launch alone. This would not exist in space.
I think a space railgun would have more power even at launch than would one on Earth.
By the time a projectile on Earth leaves the barrel, it has already lost measurable power from the initial launch.
I think we are both right. We are arguing the same point, just in different terms.


But I do see what you mean.

[Cripplecreek]

Aren't they effectively a recoilless or low recoil weapon due to the way the energy moves down the barrel rather than being produced in one spot?

[thackney]

I think a space railgun would have more power even at launch than would one on Earth.

I don't understand why you think that.

[thackney]

Aren't they effectively a recoilless or low recoil weapon due to the way the energy moves down the barrel rather than being produced in one spot?

No.  The main difference the force is applied not in a single point explosion but evenly through the travel in the weapon.  Less momentary impact but equal amounts of force returned for force sent to the projectile.

So same amount of energy slowing down the boat with a railgun, but less pounds of force applied for a longer period of time.

[240B]

I am thinking on a microscopic level, not in generalities.
I am looking at nanoseconds.


To argue that a railgun in space would perform the same as a land based weapon?
We will have to agree to disagree. Maybe one day, if we are that lucky, we can test it.


Bet you a steak dinner. lol

[driftdiver]

No.  The main difference the force is applied not in a single point explosion but evenly through the travel in the weapon.  Less momentary impact but equal amounts of force returned for force sent to the projectile.

So same amount of energy slowing down the boat with a railgun, but less pounds of force applied for a longer period of time.

@thackney

A 100lb projectile probabl'y wont have a significant impact on a 50,000 ton warship.   The projectiles in space would probably be smaller (less mass) but the force would likely be a higher percentage of a space vehicles mass.  The launcher would probably have to be fixed unless the space vehicle was massive.   The force being applied would act as thrust and turn the gun during launch, creating issues with hitting the target.

[Cripplecreek]

No.  The main difference the force is applied not in a single point explosion but evenly through the travel in the weapon.  Less momentary impact but equal amounts of force returned for force sent to the projectile.

So same amount of energy slowing down the boat with a railgun, but less pounds of force applied for a longer period of time.

That's what it sounds like to me.

https://www.physicsforums.com/threads/rail-gun-recoil.58280/

Come to think of it, mass drivers are one of the proposed methods for moving asteroids around. Mine the asteroid and fire the waste off into the space with a rail gun and dump the asteroid into the sun. (Or dump the waste into the sun and shove the asteroid out of the solar system)

[Idaho_Cowboy]

That's what it sounds like to me.

https://www.physicsforums.com/threads/rail-gun-recoil.58280/

Come to think of it, mass drivers are one of the proposed methods for moving asteroids around. Mine the asteroid and fire the waste off into the space with a rail gun and dump the asteroid into the sun. (Or dump the waste into the sun and shove the asteroid out of the solar system)

Won't adding extra fuel to the sun cause global warming? 

[r9etb]

I kind of understand what you mean, but a railgun in space would kick the ass of a railgun on a warship.
The dynamics would be completely different.

Indeed they would.  For example, there's that whole "equal and opposite reaction" thing, which (for an orbiting spacecraft) would cause significant changes to the spacecraft velocity -- and therefore to its orbit.  To a space ship, a rail gun would be nothing more or less than a thruster -- albeit one with solid exhaust.