thoughts on rail guns?
 

random link for a rail gun


http://www.powerlabs.org/railgun.htm

ive always like them being a scifi buff and all. would they actually have a practial use on a planetiary surface or just in space.

They only really have a use as turret-mounted weaponry at the moment, some sort of artillery. There aren't any power sources small and powerful enough to make handheld railguns, which would be sweet. Hell, even the techniques they have now make turrent-mounted railguns horribly inefficient.

I think that by the time they find some way to power a hand-held railgun laser output will have risen significantly as well...


so if you have hand-held laser guns, why would you need a rail-gun then?

yeah but in space.. to me rail guns would do more damage then a laser.. laser is heat.. rail gun is punch power you can light up the moon with a laser but at the distance it would be a flash light up close it would be deadly.

Being that every action has an equal and opposite reaction, would'nt a rail gun be more trouble than its worth in space?


I've got visions of some space station hurling off into the abyss after shooting off a rail gun, mebbe I'm just being a jackass tho :lol:

Railguns operate on the principal that a force is created whenever an electric field passes through a magnetic field; the resulting force (which goes in a direction perpendicular to the electric and magnetic field) is called a Lorentz force. Although in theory the railgun is rediculously powerful, there are several factors which reduce the likelihood of us seeing a viable version anytime soon. Even large-scale guns for battleships aren't feasible at the moment.

Why? Inefficiency. If I recall correctly, most railguns are around 15% efficient. That means that 15% of the energy that goes into the railgun is actually transmitted as kinetic energy; the remainder is dispersed through heat and friction. That heat and friction causes another problem; the rails typically wear down after a few shots. Given that you're transmitting orders of magnitude more current than an arc welder, it's no surprise that things can heat iup. In fact, if the bullet isn't going fast enough it will weld to the rails.

Railguns would work in space, and I don't think they would push back against the user. The force is a result of the interaction between a magnetic and electric field, and I don't think it's transmitted back to the rear of the gun. I could be wrong (maybe there's an interaction between the fields and the gun itself that I forgot).

So yeah. Railguns are fun and they shoot a lot of sparks, but unless someone comes up with a way to make them more efficient you're not going to get a lot of use out of them.

lasers have one major problem- atmospheric interferience and haze can serriously cut the power, as well as smoke and water- smoke especially, would be an effective blocker for laser weapons using the visible light spectrum- particle beam weapons however......

we're talking about in space tho... :D


and where do plasma weapons fall into the mix here?

if they had some sort of a gun that would shoot something like a plasma-cutter cuts, that would be truly kickass :thumbsup:


for those not familiar with plasma cutters:

http://www.plasma-cutter.com/technical.htm

In the immortal words of Ferris, "If you have the means, I highly recommend it"

ahh but your talking about inter atmosphere temps in space its cold real cold.. could that help in factoring the "heat cost" for a rail gun?

Newton's laws of motion would suggest that yes, there would be a recoil. Equal and opposite forces etc.

Another big problem is that the rounds in a railgun have to be non-megnatic. So you couldn't use any metals. Even aluminum is to reactive. (Almost, if not everything, is magnetic if enough force is applied. I remeber seeing on the discovery channel about an some university making spiders float with VERY powerful magnetic fields.) The rounds would have to be made out of some sort of plastic. Course no plastic is strong enough right now, so you have a rail gun that works but the round shreds the second it comes out the barrel.

Umm, don't they use tungsten to make the rounds? I could have sworn they did. Why would the rounds have to be non-magnetic? Wouldn't it just help the gun transfer more energy to the round? That way it's accelerating the round itself, along with the carrying case.

A handheld rail gun would be extremely impractical. You would have no real use for it, plus the recoil from firing would at least knock you on your ass and break alot of your bones, if it just didn't kill you. A convetional gun is much better for infantry use.

Railgun rounds are magnetic, they 'float' on the rails that carry the charge that projects them (I think Mage is right about them being tungsten). They are currently working on working models of them, the main draw back right now is the power source (they require a huge amount of power). Current power plant/ capacitor systems for them are the size of a small house. Its the same problem as with the lasers they are working on getting mounted on AC-10 gunships, they have to shrink the power source. If you have a library that stocks Popular Science there was an issue a few months back that had a cover story on advanced weaponry that talked about them as well as some of the new laser applications.

if he is right its because Tungsten has the highest melting point of (I think all) metals


I know this because the electrode thingies in Tig torches are Tungsten, so they won't melt...



edit: googl'd it, yeppers, has the highest melting point of all metals...

Supposedly, the next generation of US Navy warships will use rail/coil guns as the main deck guns.

is it a terribly good idea to use a weapon whos energy is derived from electricity (as opposed to gunpowder) on a freaking boat?
a metal boat...
floating in saltwater...


I dunno, just gotta wonderhow they are justifying it...

Because batteries and capacitors don't blow up and destroy the whole ship when their hit by an enemy round. You can insulate a rail gun very well to protect the the ship from any extraneous discharges.

The action and reaction in this case are the interaction between the electric and magnetic field, and the resulting force acting against the current flow. The force isn't actually transmitted to the railgun itself.

Sure it is, the two fields repel one another and transmit that force to the objects creating the fields. If what you said was true then there would be no resistance when you moved to to negative magnets together, they would just get really hot or absorb the energy in some other way.

Remember that the current mounts being considered for these systems are naval gun mounts (fires shells the size of a small car) and gunship mounts (Puff the Magic Dragon can carry a modified howitzer), so the recoil is less of an issue than if we were talking about something like the rifle out of Eraser (which for the record has some of the worst movie physics ever). It will be sweet to see these things deployed in a few years (as soon as they get over the energy supply issues).

When your talking about accelerating the small car to the speeds a rail gun works at, the recoil becomes a real problem even on a battleship. That is why the proposed projectiles are rather small and light compared to conventional rounds. The tungsten projectiles the military is looking at have roughly the shape and size of a model rocket, about two or three feet long, 3 or 4 inches in diameter with fins near the rear for stability. The rail gun relies on kinetic energy provided by velocity to cause damage, not mass. From the discovery channel program I saw on this subject, the rounds are actually travelling fast enough that when they strike the target, the kinetic energy released is so great that it melts the round as it penetrates. So this much smaller projectile transmits more kinetic energy(and damage) to the target than a standard round of a larger mass would.

The legendary "Gauss Rifle".

I meant that the original naval guns that the rail gun would be replacing fired projectiles the size of a small car, not that the railguns would. Other than that I agree, and like you say as a kinetic kill weapon the actual size of the projectile can be relatively small. They are considering trying to 'drop' the same type of tungsten projectile from an orbiting weapons platform as well as part of the reviving 'Star Wars' space weapons research, since it could be targeted any where and gravity would do all the work.

Yeah, from what I was reading, It's not a matter of handheld rail guns being impossible/too expensive to build and power, but the fact that firing somthing at that velocity would have some crazy recoil.. lack of arms and whatnot. Even somthing shoulder mounted would be suicidal to fire, no?

I thought this conversation would bring up somthing about 'needle guns'.. there's bound to be more than a few sci-fi junkies out there who would know what I mean. Same concept, only rather than firing somthing spherical it involves tiny metal.. well.. 'needles' that would vaporise on impact? Just wondering if there was any research into this sort of thing. It seems a lot cheaper/easier/lighter than what they're building at the moment.

The round fired by a rail gun looks more like a missile than a bullet. A rail gun can't fire something spherical because the aerodynamics would make it impossible to aim. As for a hand held weapon firing a projectile that resembles a needle more than a bullet, they have already been made. They're called flechets and the use of them has been made illegal for a good reason. They tend to "fish-hook" when they hit a person, meaning that they have been known to enter a person's thigh and exit through their arm.

Also, making the "needle" vaporize on impact would be much harder than a projectile with a much larger cross-section, the needle would penetrate, not vaporize.

Flechettes are still legal in the States; I load them as the last round in my home-defense shotgun. Anything that a 3" full of those little bastards won't stop, I want a rifle for!

You mean the Quake 3 gun is actually for real? :lol:

While in the Navy ROTC program we had an officer in the program for the Rail Gun, added to that here at UT we have a working Rail gun which is used for research.

The Rail Gun is currently being tested by the Navy. Yes, they use Tungsten, it's about 8-12" long, basically a tungsten rod with a pointed end and little fins that are intended to pop out after firing.

Anyways the Navy fired one into the desert a couple miles away, onto a concrete target on the ground. I cant say how successful, it's classified, but let me tell you it puts 155mm howitzer to shame.... and it's just metal, no explosives.

I thought that the rod was made with the fins in place, not retracted. As far as I remember seeing, the rod was launched in a module that split off from the rod once it left the "gun". So correct me if I'm wrong, but I thought that was how it was.

And with the new power supply they are supposed to be working on for the new DDX class Destroyers, they will have all the energy they need. From what I hear, these things are going to be SICK. Now what I REALLY want to see, is a supercavitating version of the sucker for sub hunting. We've already broken the sound barrier underwater with supercavitaion. Can you imagine what a mach 2+ round would do to a sub. Gives me shivers just to think about it.

i dunno how feasible hand-held rail guns would be, but i just have the image of someone standing there with a huge implanted rail gun on his arm blasting away... that would be awesome

correct me if I am wrong but there should be no recoil from a rail gun. The recoil from a conventional powder actauted gun is due to the explosion that moves the round. The rail gun is in its basic terms a magnetic field being moved froward along a rail thus dragging the projectile down the rail until it clears the end of the rail no explosion just an object being dragged.

If anyone has information to the contrary please say so i would like to know for sure.

Thanks

No, railguns do produce recoil from the look of it. Aside from Newton's 3rd Law, and just thinking about it, I looked it up on numerous sites (some scientific, some speculative, etc) and they all said the same thing; recoil will be produced.

But what causes the recoil I look at a rail gun as a basic pull toy. You lay a piece of metal (with a pull string on it) in a channel. Then you pull the string jerking the metal out of the channel. The projectile is basically supported on a layer of magnetic waves so it is not generating any force on any part of the actual rails and the propulsion is produced by electrical energy traveling up the magnets around the rail. It may cause so sort of recoil but I don't see how it does it. Other than the fact that the weight of the projectile is removed from the rail at a high rate of speed causing a shift in weight but not in the sense of recoil.

Sort of ignorant on the subject I might not have all the information I need to think this one through.

Well I'll try to put it into simple, and hopefully correct, terminology:

Say you're trying to pull or push an object and you're floating in a vacuum (suspending the whole biological impossibility of it). You have nothing to resist against, so you can't move the object without moving yourself as well, correct?

Same thing applies to this magnetic force. It has to push one object away from another. In the case of a railgun, it is pushing the bullet away from the magnet. As the magnet pushes on the bullet, the bullet pushes back on the magnet. This pushes the whole gun into you. The only reason the bullet goes forward and the gun doesn't go backward (not too far at least) is that you're there to resist the push of the bullet.