I wish to start a project that uses powerful magnets to propel a bullet through at high speeds without using electricity. The design would include a barrel made of completely magnetic materials to eject a bullet out of the barrel at high speeds using neodymium magnets and magnetic bullets. I understand the forces between two powerful magnets made of neodymium is incredibly large even with a low amount of mass. Could the forces involve possibly create enough velocity to propel bullets at high speeds?
No, that's why electromagnetic force is used, and the energy is applied along the rail/barrel.
I am not sure how to explain this fact, but lets look at simple numbers:
The energy of Neodymium magnet is 512 kJ/m3 max (Wiki), which gives around 10 Joules of the stored energy in a handheld bar. The muzzle energy of a pneumatic toy riffle is around 20 J, while .223 Remington is designed for 1.3 kJ.
However you can create some shooting and jumping toys for raising kids curiosity.
Very interesting research field, Tyler!
I have the feeling that Andrey could be right. However, please keep me informed: fascinating issue!
Alberto
You can actually represent this as a potential energy/kinetic energy problem. The potential energy between two magnets is converted to kinetic energy if they're allowed to "fall" together, and converted to a significant amount of heat if they actually impact. Now envision creating a vacuum lined tube going through a hole in a large neodymium magnet. Your neodymium "bullet" would sit in the tube and be released to accelerate towards the magnet, converting the potential energy of the magnetic pull into kinetic energy (velocity) as it passed through the magnet. However, as it passed through to the other side, the pull would reverse and it would slow down, converting all that KE back in to PE, until it stopped and fell back again and again. Assuming no friction, this would ideally continue forever, although in reality it won't since you've created an oscillating magnetic field which, oops, radiates EM waves and thus energy is lost as radiation!
Railguns use oscillating fields to apply attraction and repulsion at appropriate points in the trajectory of the projectile and accelerate it constantly. Basically they're just a linear electric motor. A magnet is not a motor. You have to alternate the fields somehow. Spinning a magnet might work if you did it right.
And BTW, before someone makes the connection between gravitational PE and magnetic PE and then asks, "So how does gravitational slingshotting work for the space program?!!", that's a transfer of angular momentum, not gravitational PE. The planet, Sun, etc. slows down slightly in order to accelerate the spacecraft. Spinning the "drive" magnet to first pull and then repel the magnetic projectile as it passed would require the same amount of energy to rotate the drive magnet that was imparted to the departing projectile.
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