Ok, my Remington speedmaster's receiver was slowly losing it's blue over time. I blued many barrels and a few receivers before. I always use outers gun blue that you wipe on with a sponge brush and it comes out great. So I sanded my rem's receiver with very low grit to get the bulk bluing off, then I used steel wool (always do this). So as I'm spreading the blue on it started turning a muddy brown! Then I saw fumes come out and it stunk and burnt my nose. WTF happened? Are these fumes harmful. I think the receiver is made out of different steel so it reacted differently. What can I do to blue this thing guys? Thanks.