What are they? Are they hard to make? Expensive? All I know about them is what a friend told me about them, that that can be very powerful & he thinks they run on magnets? They sound interesting, Would make a nice project.

From what little I've heard they are run from electromagnets and require very large voltages. I think they take quite a bit of time and effort to make, but if you build one properly it can be very powerful, capable of firing nails through trees and such.



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Day must fade to night,
Night must give in to sunrise,
I watch, silently.

~A Haiku, Minami Sasake

more commonly called a rail gun, any small enough to be useful isn't powerful enough to be and visa versa the main use currently is in impact simulation of astronomical bodies.

Last i'd heard they were trying to fit one onto a tank chassis. Obviously still quite along way to go before the hand held rail gun that is actually useful

"more commonly called a rail gun2 Wrong! a gauss gun is a coil which a projectile is accelerate though (sling shot sort of) a railgun uses 2 parrellel rails which when a current of a few KA+ it pulsed though creates a intense electromagnetic field that pulls any projectile between the rails out of the gun. http://joe.wangism.org you can see a guass gun on my site, it is a VERY inefficiant one though, i should beable to get 6X the efficiancy out of it by modifying the coilform, as railgun is also coming soon.

the only advantage electromagentic lauchers have over conventional chemical proppellents is that they send a projectile to hypervelocity where as chemical proppellents cannot.

oh and the are some railguns and coilguns mounted on US battle ships i think the fastest one goes at something like 13km/s

Yes indeed one thing is certain both coilgun and railgun are far more powerful than the classic chemical propelled projectile systems .The hystory of both system is long and it is not the case to tell it right now but what is certain is that large scale experiment for the development of the initial idea have begun during Regan administration the ocasion the well known STAR WARS.Theoretically speaking the scientific principles on wich those two weapons rely are simple(railgun-lorentz and the coilgun is based on the gaussian laws and it represents the basic interraction between an electromagnet and an ferromagnetic material) and therefore accesible to all of us ,of course at demonstrative level bicause both processes
require a large amount of energy and specially high currents from amperes to kiloamperes.1Railgung are made from 2 rails preferablly from highly conductive materials such as coppper a slug wich must also be made from a highly conductive material(graphite)and in the end in the end the hi current power source.2Coilguns are made from one or more solenoids and a ferromagnetic slug that travels driven by the electromagnetic field riht trough the solenoids and of course a hi current power source.But enough wich the technical details u can find more answers on this page: http://www.jamespaul.clara.net/coilgun/links.html

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EVOLUTION TROUGH PERTINENT SCIENCE

By the way about the cost; the cost of the entire system is relative low but the most expensive parts of the entire system are the hi voltage/hi cappacity capacitors but nevertheless the cost of the system will increase with the builder's lack of knowledge that's why i advise u to be very cautious in the process are involved large amounts of energy so be advised.To end this reply ..the army already uses systems such as those from about 10 years but there is a rummor about portable systems .
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