It as been done but they gennerally won't do it because they can't garnutee the finish if it hasn't been baked on at high temp. Some people have gone to the trouble of stripping scopes down to thier bare metal componants, prepping the parts, coating them , baking them and reassembling the scope..... big task.
Gun control requires concentration and a steady hand
Yes you can but I hate doing so, especially with high end scopes. The reason we use C series CerakoteTM as correctly stated is an air cure product. Standard H series Cerakote is an oven cure at 120Deg and is super strong once cured. Even a Low temp bake at 88Deg may compromise the Nitrogen gas to expansion and blow out the seals. C series is still way better and longer lasting than ordinary 2K paint, but it will take 5 days to fully air cure to achieve hardness. With a scope you have to sand by hand. No way im putting that into the blaster.. Cheers WWC