I would like to make my own heavy duty snaps (my design). Does anyone know what kind of wire the big companies like Berkley and Sampo use and where I can purchase some?
Changeling

I dont' know what kind of wire they use, but if you want to try it, but a few SS welding rods in various thickness's and see what you can do.

Unless you can heat treat materials it ain't gonna work.

Those are annealed, then formed, heat treated, then tempered if needed to get the stiffness (springyness) in them.

You can try stainless steel spring wire from MSC. I use it for my plugs and it's tougher to bend than the anealed welding wire, but in the bending process you may be weakening the wire and it will be difficult to bend into small shapes.
Bud8fan may know what you can use or the techniques of heat hardening. He's the metal man.

Chumbucket thanks for the reply. Who is MSC?
Changeling

i think it is MSC industrial supply Co. 1800-645-7270

www.mscdirect.com