[Herb]

I have used carbureator cleaner, brake cleaner, laquer thinner, acetone and just about any other cleaner at hand on my pistols and have yet to harm the blueing. If you use rust and bluing remover it will definitely do the job of getting that nasty bluing off. Some of that stuff used in the numbers and proofs is water based, just use a tooth brush and hot water and soap, others are chemical based and will require the first items I mentioned. If you are still squeemish use Hoppes #9, that should do the trick and it's made for guns.