A cold bluing question.

I recently reblued a Webley Mk3 . It was a ‘deluxe’ edition with a superb factory chequered stock, but some damage had occurred to the receiver and the whole receiver/barrel assembly had be deblued and roughly polished (the impressed lettering worn down in paces, and couple of dinks in the tube).

Too good a stock to leave with such a shabby action I decided to have a go at my very first large scale rebluing.

So I followed the text book, removed remaining bluing, polished the metal surfaces, degreased everything and then lightly warmed the metal before applying Brichwood Casey Superblue. The barrel, underlever, cocking link, loading tap cover and arm worked a dream, a deep black almost Webley like coverage was the result, very happy.

Next day tried to complete the main receiver tube and trigger housing. All had been polished, degreased and warmed. Big disappointment best I could achieve was a blotchy dark grey with black spots. What did I do wrong, any ideas? Best I can think of is that whatever damaged the reliever to necessitate the original cleaning by previous owner somehow altered the properties of the surface steel. Or is it that the rear sections are made from different steel.

Will have to do it again, though it looks vastly improved, but any tips?