Seems like you could make a gauss long gun. Make the barrel about as long as a healthy long rifle, on the order of 1 meter. Carry the batteries and most of the capacitors in a backpack. Run heavy wire to the gun. Instead of having 2 coils, have 20-50, each accelerating the projectile. Sure, it’d be a wee bit hefty, but I bet you can get it to put out a lot more than 3.8j.

Posted at 10:29 am on Sep 3rd, 2005 by billytheimpaler

Holy crap. I WANT ONE!!!

Posted at 11:26 am on Sep 3rd, 2005 by Kenny

http://www.pskovinfo.ru/coilgun/indexe.htm

the original

Posted at 1:02 pm on Sep 3rd, 2005 by matticus66

a long coil wouldn’t work; in fact, it would cause a loss in efficiency because of eddy currents. as soon as the projectile gets half-way through the coil, if there is still current flowing through, which it’s likely there will be because a coil is an inductor, and in this case, a 1m long coil would have a lot of inductance, the coil will actually pull the projectile backward and slow it because the inductance keeps the current flowing through the coil for a short time after it is on longer being powered.

also, having simply more capacitors or larger ones may have a similar effect on the projectile because they may not discharge quick enough, thus causing prolonged current through the coil which will hold the projectile back if it’s on for too long.

another good idea is to use a solid state switch like an SCR so that there is not spark. the reason you dont want a spark in there is because it essentially wastes energy by bridging the gap between the two electrodes in a regular switch. when looking for a solid state switch like an scr or transistor, be sure to check ratings on it for the application; too low of a rating, in an scr, can allow the current to leak through if the voltage is over the scr’s breakdown voltage, and for a transistor, with too much current, it’ll fry easily.

The Pskov 1100 is a really good design, so if you’re going to make one, i’d suggest looking at that (the guy before me posted the link).

good luck, have fun, dont hurt yourself or anyone else

Posted at 1:27 pm on Sep 3rd, 2005 by m

m,
I think billytheimpaler was talking about using several coils along one meter (he said 20) instead of 1 really long one. Unless i misunderstood what you are saying, i was under the impression that if you had some sort of sensor (like an optical beam) between the coils you can shut off the coils as the projectile travels through the barrel. Or would inductance still be a problem? Couldnt you just time it so that it would shut off the coils early?

Posted at 2:24 pm on Sep 3rd, 2005 by stillboy

interesting you mentioned that, stillboy.

http://www.coilgun.eclipse.co.uk/16_stage_opto_prototype.html

Posted at 2:39 pm on Sep 3rd, 2005 by mark

It sounds somewhat unlikely, but I suppose this could be used to knock somebody out with a shot to the right place (and the right kind of projectile). But that might just be my brain being corrupted by games like Splinter Cell (and my lack of knowledge of what projectile is actually being fired by this thing).

Posted at 4:18 pm on Sep 3rd, 2005 by wildweasel

try not to shit your pants
http://forum.4hv.org/index.php?board=5;action=messageindex
the 4hv forum on coilguns/etc

Posted at 5:13 pm on Sep 3rd, 2005 by ...

The site now says… and I quote…

“Site Temporarily Disabled
This site has been temporarily disabled. If you are the owner of the site, please contact customer care.”

seems we killed it with too much traffic

Posted at 5:51 pm on Sep 3rd, 2005 by slymer

Another bit to consider is that as you add coils you get less bang for your buck. The faster the projectile moves, the less time the coil has to act upon it. And as others have stated, this can slow the projectile down.

Remember, a coil can only provide magnetic suction. That is, elec current in a coil will draw the projectile toward the center of the coil. If current is flowing after the projectile passes the center point in the coil, the remaining energy will slow dowh the projectile.

Posted at 5:56 pm on Sep 3rd, 2005 by Enterrupt

goody! now all we need is a warthog and some pissed off, fanatically religous militant aliens.

Posted at 12:36 am on Sep 4th, 2005 by yay, guns

World’s Coilgun Arsenal
http://www.coilgun.ru

Posted at 6:24 am on Sep 8th, 2005 by Evgeny

That is a nice gauss gun. Amazing how 1 or a few people actually build those things as oppose to the number of people who say “I plan to build” (forum.4hv.org) Those poeople are just a wast of time and keyboard typing.

NOw here is the heart of coilgunning, not the original, yet what fed the spark ablaze all around the world. Here –>
http://www.anothercoilgunsite.com

Posted at 12:46 am on Jan 25th, 2006 by rupidust