I bought this gun, 1937 vintage Win 94. The receiver has mostly a brownish, gunblue color, and I am sure that it is not patina, but cold blued of some sort. HOWEVER, there is a definite greenish, or greenish blue cast to it in spots. It tones down when I clean with solvent, but as soon as oil is reapplied, the green comes right back. What could have caused this greenish hue? How do I solve it? I did try some 0000 steel wool in one small hidden area near lever, and it helped some, but of course dulls the finish, so if that is the only answer, I would need to do whole receiver evenly.
Thanks, David M

I bought this gun, 1937 vintage Win 94. The receiver has mostly a brownish, gunblue color, and I am sure that it is not patina, but cold blued of some sort. HOWEVER, there is a definite greenish, or greenish blue cast to it in spots. It tones down when I clean with solvent, but as soon as oil is reapplied, the green comes right back. What could have caused this greenish hue? How do I solve it? I did try some 0000 steel wool in one small hidden area near lever, and it helped some, but of course dulls the finish, so if that is the only answer, I would need to do whole receiver evenly.
Thanks, David M


Some cold/touch-up blues (esp. in the past) have some copper compounds in them...on a guess, someone's old touch-up blue is the cause of the green.

Some cold/touch-up blues (esp. in the past) have some copper compounds in them...on a guess, someone's old touch-up blue is the cause of the green.

Thanks,
Would I be advised to try to remove those spots mechanically, like 0000 wool, or would I be best to remove everything with a chemical blue remover? I would like to keep the older looking patina look, and thought perhaps with steel wool I could just "blend in" those areas. Probably won't work that way.
David

Thanks,
Would I be advised to try to remove those spots mechanically, like 0000 wool, or would I be best to remove everything with a chemical blue remover? I would like to keep the older looking patina look, and thought perhaps with steel wool I could just "blend in" those areas. Probably won't work that way.
David

David, To get rid of the green cast, you will have to get rid of the copper contamination. Mechanicaly would involve taking the area down to bare metal, loosing any original patina. You might try an ammonia solution before trying any rhing mechanical. A lot of the older cold blueing solutions contained Copper Sulphate that creates a thin copper coating that oxidizes to black after application.

As for blending in those areas with steel wool, forget that idea, as any oil will react with the copper and come up green.

Seeing as how you have a 1937 vintage 1894, it is possible to remove all finish from the affected area. (receiver) and put down a nice low luster 400 grit finish and use a cold rusting process that can be boiled in de miniralized water that will turn it black, and almost match the original finish.

That vintage of a M94 sounds like a good gunsmith rebluing project to me.

That vintage of a M94 sounds like a good gunsmith rebluing project to me.

I will try the ammonia solution and go from there. Thanks for your answers and advice
David