I have a Knight LRH, stainless steel, that I am in the planning stage of scope mounting. I have a set of Burris ss mounts, but have noticed that they are a bit more shiny than the barrel.
Has anyone experimented with any methods to dull the mounts/rings? I am contemplating sandblasting them to see if it will dull them any. Maybe dipping them in some type of chemical? I have seen several guns in which the ss mts/rings don't match the barrel; most aren't very close.
Any suggestions?

No expert in this regard, but I would rough them up by sandblasting, emory cloth, etc; but I wouldn't use any chemicals.

boil in baking soda solution for 30 mins er so... we do this with snares