Mr. Marrakai:

Much obliged for the information.

This is a very early Gibbs action and besides the two .461 Gibbs cartridges, which don't excite me much, the only chamberings shown in the Gibbs catalog were the .500 BPE and the .577. I can't say as how I have any need for a .577, but it is the most interesting of the options.

Thanks again,

Glenn