Granadier

Grenadier and Daryl S. i thought this very carefully and decided to go the other way. Siamese will be passed on to somebody that wishes to build something on it. I have another project started, Winchester 1914, was 30-06, now has .510 bore barrel installed. I am searching for caliber to chamber it in ? Then will mill bolt face to that size. Action is done, Mag is pot-belly Nitro Express type. It has to be factory type cartridge, so brass will be easy to find. I have friend that custom-loads all of my ammo. Any suggestions ?