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[Parsely]

Hows about a clip of railgun rails, with each pair or rails ejecting to be replaced with the next from the clip after becoming too worn? Again, not too useful for an infantry weapon...

Why do you need to replace the railgun rails?

[Amperzand]

Because they last for about five shots.

They get really hot and burn off mass every time you fire through them, and it only gets worse if you fire the same barrel repeatedly.

[Parsely]

Because they last for about five shots.

They get really hot and burn off mass every time you fire through them, and it only gets worse if you fire the same barrel repeatedly.

Oh I see, because of the electricity. I was having a hard time imagining why they have any more frictional limitations than other guns.

[Rolepgeek]

They have to be in contact with the edges the whole time, and go at much higher velocities than conventional weapons. Even smoothbore, it has to stay in contact with the barrel to go faster. To be powerful enough, they have to go very fast.

I figure using a plasma conductor/charge that propels the projectile from behind might help with the actual fatique, if not the heat. Maybe the heat. I dunno.

[Amperzand]

Basically, the things work by using the slug to short out a really, really powerful circuit, which produces huge electromagnetic forces of the sort that don't really care what it is they're accelerating so much as that it's in the way. In the process of doing this, they produce a massive continuous electrical arc on either side of the slug, severely damaging it and the barrel. For this reason, the slugs are usually held in an aluminum sabot during firing, but that doesn't help the barrel much. Fortunately, railgun barrels are pretty cheap, due to being just metal rods. I wouldn't be surprised if you could use literal train rails, actually.

Edit:

Spoiler: All that fire is basically bits of the barrel and sabot, AFAIK (click to show/hide)

[Rolepgeek]

Well, Amp, the way the force pushes, those rails have to still be strong enough to make it so that the projectile is the thing being fired, and not them. The force pushes on all directions, not just forward+recoil. If they stop being in contact, it kinda ruins the point. Also, if you don't have a good enough conductor, it's gonna be a lot more energy intensive and a lot more damage on the barrel(if you don't care about barrel damage, at least care about how many you can carry with you, and how many shots you'll get for each set...)

[Parsely]

Basically, the things work by using the slug to short out a really, really powerful circuit, which produces huge electromagnetic forces of the sort that don't really care what it is they're accelerating so much as that it's in the way. In the process of doing this, they produce a massive continuous electrical arc on either side of the slug, severely damaging it and the barrel. For this reason, the slugs are usually held in an aluminum sabot during firing, but that doesn't help the barrel much. Fortunately, railgun barrels are pretty cheap, due to being just metal rods. I wouldn't be surprised if you could use literal train rails, actually.

Edit:

Spoiler: All that fire is basically bits of the barrel and sabot, AFAIK (click to show/hide)

Source? I'm interested in reading about these mechanics in further detail.

[Amperzand]

Well, Amp, the way the force pushes, those rails have to still be strong enough to make it so that the projectile is the thing being fired, and not them. The force pushes on all directions, not just forward+recoil. If they stop being in contact, it kinda ruins the point. Also, if you don't have a good enough conductor, it's gonna be a lot more energy intensive and a lot more damage on the barrel(if you don't care about barrel damage, at least care about how many you can carry with you, and how many shots you'll get for each set...)

Oh, certainly. The mechanics just do work as long as the bits are all present and correct, I'm hardly suggesting you could build a military railgun out of forks and nine-volt batteries.


@GUNIN: Wikipedia to begin with, plus a bunch of random stuff I can't remember in specificity. A good general source for mil-scifi things seems to be the AtomicRockets website.

[Tack]

If the sabot is basically a lost cause anyway, that'd explain why it's made out of (relatively soft) Aluminium?
So would making the barrels from tungsten or some other high-tensile carbonised alloy be an improvement longevity-wise?

[Parsely]

If the sabot is basically a lost cause anyway, that'd explain why it's made out of (relatively soft) Aluminium?
So would making the barrels from tungsten or some other high-tensile carbonised alloy be an improvement longevity-wise?

According to wikipedia it's beyond current materials science to make rails capable of withstanding several shots per minute without severe degradation and permanent damage to the barrel. But I can't find any credible sources to back it up.

[Amperzand]

Basically, the forces and heat involved are just really, really silly. I'd imagine things with the thermal resistance to absorb it without partially vaporizing are too brittle to handle the physical blast.

[Insanegame27]

Coilgun master race, oi oi oi!
While you may not be able to make a railgun out of forks and 9v batteries, you can make a relatively lightweight coilgun pistol out of relatively common materials, including the capacitors from about 40 Kodak (or similar brand) disposable cameras and using plastic straws as stabilising fins for the rounds.



www.instructables.com/id/How-to-make-a-coilgun/


Like the disclaimer in the link, I am NOT responsible if you hurt or kill yourself.

[MonkeyHead]

Coilgun master race, oi oi oi!
While you may not be able to make a railgun out of forks and 9v batteries, you can make a relatively lightweight coilgun pistol out of relatively common materials, including the capacitors from about 40 Kodak (or similar brand) disposable cameras and using plastic straws as stabilising fins for the rounds.



www.instructables.com/id/How-to-make-a-coilgun/


Like the disclaimer in the link, I am NOT responsible if you hurt or kill yourself.

I have actually gone and done this. Using basic 10mm plumbing gear as the barrel, narrow gauge copper mains wire, and a bunch of 1 Farad capacitors form dismantled base speakers, I constructed a relatively scary device that could fire ball bearings and iron nails at a decent velocity. Not enough to do more than bruising, which was probably for the best.

[Insanegame27]

I used to have a crow problem, put it that way.

[Amperzand]

Coilguns are pretty simple to make at that simple level, with railguns, AFAIK, being even simpler physically, but harder to make because of the more dangerous forces involved. The issue is that neither is up to chemical-ballistic standards as of yet.