I am looking for cast bullet loading data for the 458 MCW Express.
It is a full length 375 H&H blown out to 458. (designed in 1953 by Macfarland, Corbett & Wells all of prescott, AZ)
The manuals I have do not list this cartridge or any of the similar cartridges like 458 Lott, Barns, Watts, Mashburn or 450 Ackley Magnum using cast bullets. Ackley's Handbook vol 1 shows some maximum loads for jacketed bullets but nothing cast.
If anyone is loading for this cartridge or can suggest somewhere I can look it would be appreciated.
Thank You, Bob