Well, it doesn't matter if I could spin stabilize it or not for the time being cause my dremel made a liar out of me, I can hollow out the base of the rounds, it just takes patience, but it paid off, might upload a picture sometime soon.

Because of the way the ammo is fed anything attached to it would make it too long, and I cant do anything else. But, i just looked some rpm rates for various bullets and twist rates, yeah they are in the hundred thousands to stabilize just .22's. So yeah, things dont look good for my idea, unless I ...

What about a weak electromagnet attached to one side of a tube that rotates around the barrel, sorta like my original design?

But would you say it would work? Because I know that you dont have to have a working idea to get a patent. Do you think a low powered electromagnet would work with an unmagnetized projectile?

Good thing I didnt build it then, mr. sneaky :p. Can't wait to see what you do though.

Maybe something to do with this?

@ Geardog- I thonk the nail would snap in place with the poles lined up and just come to a complete stop.

24mm long sections of steel nails, almost the exact same diameter as 6mm airsoft bb's, but I can't be exact as I don't have anything to measure them with.

I don't have the tools to make a hollow tailed projectile sadly, or really anything. I have a dremel and a drill to make things with, plus being convoluded is fun. But if I could make them I would.

I'm building a multi-stage coilgun for a science fair project, and am about to add a third stage to it and was wondering if spin could be applied to the projectile without rifleing or modifying the projectile, thats when I came up with this: http://i790.photobucket.com/albums/yy186/grunt009/Picture0...

The barrel of the railgun is 3', the injector barrel is 3', but they are both in the same enclosure.

@Ramses: I planned on having my friend(certified welder) weld the spark plug into the chamber along with the rest of the injector, so I don't have to worry about any threaded parts. As for the fuel meter I don't have any parts, but I do plan on making it detachable(so I can use it on my other potato...

How come everyone can find things cheaper than I can? How much did you spend the materials for your gun, if you care to remember and break it down? If anyone knows where I can get anything for less, do let me know, I would appreciate it very much.

I figured I might as well post my bill of materials and see if anyone can see anything I might be missing(aside from materials for the charger and the flange, and stun gun, which I already have): x1 Fiberglass sheet - http://www.mcmaster.com/#3345k44/=1ug10h x1 Fiberglass sheet - http://www.mcmaster...

I think you guys are right I just went back through all the math and figured that I might go with a 3' or 2' gun for the cost. But to further reduce the cost I might use electrical grade fiberglass, but anything that needs to be cut I can do at my school's shop, so no machining costs. A 6'x1/2"x3" p...

I think what I'll do is have the entire railgun be 7' long, 4' for the railgun and 3' for the injector. As per the HGDT sim, this should be able to accelerate it enough so that the railgun can bring it past the speed of sound. As for the cooling what I want to do is have the fridge compressor just p...

As you may or may not be able tell from the title I plan to build a railgun (or Linear Electromagnetic Accelerator) for a science fair project. I was recently accepted into the South West Virginia's Governors School. They hold a Science fair there every year entering a railgun as my project. My idea...