Thread: birchwood cold bluing turning to rust one week later

Only thing I'd suggest is go for the finest you can find - replacing 0000 is ideal (I think that's purple grade?).

I know everyone is saying don't use steel wool, but I don't find any issue with using it provided you clean it properly and oil it after neutralizing the chemicals in the mix.

I suspect that if your product isn't colouring the surface of the steel there is a contamination issue or a coating of some sort interfering with the chemical reaction. All I can suggest is find a piece of mild steel, clean it back to known bare steel (i.e. you know there's nothing contaminating the steel) and try a few patch spots. Use one with the treat, neutralise, clean, treat method - a second with the technique of multiple coats then treat, another as a one treatment clean and no oil and another as your 'control' cleaning it back and doing nothing just to see how the product works in different treatment styles to get an idea of the best way to go forward with it on your barrel.

Edit - just thought of another possibility, unlikely but if your steel has higher percentages of some of the alloying materials it might be very difficult to get a proper colour match. I know with one Rem 700 barrel I had slimmed and threaded to fit an overbarrel suppressor I already had, Dean Maisey chucked on a couple of coats of cold blue which really did nada to match the sandblasted oxide finish that Remington used. I had to do multiple coats, not cleaning between (product on product technique) to get it to take the colour but finally got there after about a week. Painful...