I will agree with Whitworth. I don't like a Bisley but MR has one that is different, there is room behind the guard for my huge finger.
Just get the .500 BFR, no funny size bullets or brass. Cost is about the same as the .475. I think it costs me 13 cents a round and the .44 is a dime. I cast my own and made the molds. Cuts the cost down so I let everyone shoot all they want. Recoil with the .500 JRH seems less then the .475 with less torque. But both are great for hunting.
You just can't walk into Walmart and buy a box.
Whitworth brought his gun here and made me a believer so I cut a mold and did this at 50 yards working loads.
By the way Whitworth, I still have the .500 Linebaugh mold. I can mill for an RCBS or Lyman handle since Rapine handles are gone when Ray retired. You can have it free. Let me know.