JD62- Thanks! I learned a lot by browsing through Will Ghormley's work. Looking at his stuff is what got me interested in Sheridan Carving.
Gary PL- the cup is a wax bullet deflector... odd, I know. There is a group called the Cowboy Fast Draw Association, that does fast draw shooting, but the bullets are wax and the charge is just a shotgun primer- no actual propellant. Apparently they get to really cranking on those 6-shooters (the serious competitors all draw, cock, shoot, and hit the target in less than half a second) and sometimes send a wax bullet down the leg. Not fatal, but embarrassing, and it can leave a bad blood bruise.
Anyway, most of the companies that make holsters for their game have metal bullet deflectors. I got to playing around to see if I could make one entirely out of leather that can stand up to repeated wax bullets being fired into it. The cup you see is the final iteration of that design. Thanks for asking!