my local gunsmith who does excellent bluing did my .54 cal custom ML barrel for me and he didn't like the way it came out. He told me to bring it back after the season (last year). There were areas that didn't take the bluing that well and he used the same batch of bluing on other firearms and they came out nice.
I had some time a couple weeks ago and nothing to lose so I degreased the barrel then rinsed it in warm water, dried it and applied Birchwood Casey's Perma Blue Creme per the instructions. In just 2 coats with light steel wool buffing in between and the barrel came out excellent. I couldn't have asked for a better job.