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how to make a railgun at home? Answered

i would like to make a railgun at home, but i need to know how many capacitors, how to make the rail, etc. i was hoping to be able to do it with disposable camera parts. there is a tutorial on here on how to do it but i cannot get enough information from it to be able to build one. It would also be nice if it was considerably powerful. any help? 


Have you considered using small arms instead?

That adjective is somewhat misleading since small arms; i.e.  pistols, rifles, etc, are actually quite powerful. 

I think the numbers you want to look at are the muzzle energies, like in this table:

This muzzle energy is the actual kinetic energy of the bullet as it exits the muzzle of the gun, and from that table you can see that typical muzzle energies are in the range of 100s or 1000s of joules.

The amount of that can be energy stored in a typical photoflash capacitor is usually in the range of about 10 to 20 joules.

The goal of a gun, of any kind, is to convert stored energy into kinetic energy in a projectile, and the conversion happens quickly, well, explosively  would be a better word.

What was the line that movie/novel, "Fight Club"? 

"A gun is a tool for focusing an explosion in one direction."

Something like that.

Anyway, I don't want to bore you with the physics too much, but I think a good place to start might be with the equations for the energy stored in a capacitor, U=0.5*C*V^2, and the kinetic energy in a moving mass, U=0.5*m*v^2.  The quantity of energy you can store puts an upper limit on the amount of energy you can convert into the kinetic energy of your bullet.

The Wikipedia article on Pulsed Power might be useful too, since that is kind of electrical power, i.e electrical energy converted quickly, er explosively,  the kind needed for to power a rail gun.

Soooooooooooooooooooooooooooooooooooooooooooooooooooooo many capacitors. like, dozens or hundreds of farads. But be careful, there's a thousand ways to die in the ways of the railgun.

Railguns use Megawatt discharges. What do you think you can manage with a few caps ?

Also, the big guys are dumping energy stored in rotating machinery, not capacitors.

You will get more information if you entre Rail gun as your tags rather then Disposable Camera