Hi ken

Thanks for the information. Ill try an aqua regia solution on them and see how it progresses. I remember reading somewhere that this can slightly matt the steel so I avoided it cause Im aiming for a high polish finish but now you recommend it Ill have a go.

Im also going to find an off cut of some shotgun tubes and try the ferrobronze mix on them as well. This should be more in-keeping with the barrels i eventually want to black. I guess I thought one mix should work on most steel but this clearly is not the case and you have to adapt to which barrels you want to black.

Thanks for your time and knowledge