How do MOSFETs work for coilgun firing circuits?

[SaraR]

I am trying to use mosfets to fire the coils on a coil gun I am building, I started with SCRs and have switched over due to problems. Does anyone know how they work it has been like 3 years since I took a class in analog and I can't remember for the life of me. Thanks for any help in advance.

 

[chroot]

For n-channel FETs, you apply a positive Vgs > Vth to turn them on. For p-channel FETs, you apply a negative Vgs < Vth to turn them on.

- Warren