ihatedumbpeople: Didn't "Eraser" and a dozen other movies do this?

yes



/only good part of that movie
//besides Megan Fox's tits

Super weapon is a bit of hyperbole. It depends what and where its railing. Rail gun on a naval destroyer launching sabot slugs, like we're testing right now. Badass. Rail gun on the moon launching captured asteroids. Super weapon.

Cyno01: Rail gun on the moon launching captured asteroids. Super weapon.

1. your confusing a railgun Railgun with a Coil Gun. similar principles but distinct ideas (equally cool)

2. looks like someone has been watching Justice League cartoons recently

Until somebody shows up with one at Knob Creek, it didn't happen.

netweavr: Satellite launches just became a ton cheaper and easier

Um no. Not unless you like your payload smeared all over the back of the housing. That 33 megajoules is the about the same as hitting it with the force of 33 sticks of dynamite. Over several milliseconds.

meanmutton: EddyKilowatt: Isn't the railgun kind of the Electric Vehicle of projectile-throwing technology? Higher cost, lower performance... and minus the planet-saving aspects that make EVs potentially worthwhile.

Higher cost, theoretical higher performance... plus the sailor-saving aspects of not having to carry around high explosive artillery shells.

Yes and no.

First off, the explosives in the shells themselves are child's play compared to the explosives needed to propel the shell.

And all you are doing is changing how you are storing the energy. Now instead of having the energy in cordite (or whatever they are using today...) you are storing the equivalent energy in the form of fuel. Fuel that has to be converted to electricity. And electricity that must be stored in a relatively quick release form.

Now I don't know if you've ever played with a bank of capacitors. But let me tell you, they can do a pretty good job of exploding too. Not to forget arcing, electrical fires...

It may be less risk than storing explosives. But it's not risk free.

MechTard:
You would need to do some pretty special engineering to make it work, and your barrel would be REALLY long (to spread the acceleration) but the Air Force is working on using EM propulsion (rail/coil gun tech) to launch payloads into orbit. More or less, a really long barrel and a special sabot encasement is supposed to do the trick.

On the moon.

As soon as something traveling at that rate of speed encounters air, it's going to slow down considerably. Not to mention heat up. So unless your really long barrel extends out of the atmosphere, your craft is going to need engines to maintain the momentum gained by using a rail gun.