I have a Westley Richards Gold Name with nitro proofed Damascus barrels. The bore dimensions are marked 12 over1 and the bores both measure .739. Am I correct that 12 over 1 is .729 + .010 for a total of .739? The bore are bright and shiny. Is there any reason I should not use RST, Gamebore and B&P 2.5 inch ammo in the gun? How about Winchester 2-3/4" extra light?