heres the problem have a marlin 336 in 30-30. Haad bbl slugged and it was a hair over 308.Was going to order vast bullets sized at 310 but now since finding out about powder coated bullets I'm now confused on what size to order the cast bullets.I understand that PC the bullets adds to the dia.So if I order a 309 cast and PC it will id mic out at 311.Just need answer to which cast bullet to uce in a micro groove marlin with a 308 bore.