Well, Sneezy, might try Laurel Mtn again some day. Had an Ed Rayl pistol barrel & tried Laurel Mtn; after about 4 coats of daubed on solution, still had a real blotchy job. Instructions say don't rub: heed the warning, as my rear sight got a kinda coppery look. Finally took it all off, found the dregs of a bottle of Wahkon Bay solution & used that.
I prefer the Wahkon Bay solution, but they went out of business due to governmental regulatons (so rumor says). Found out another outfit bought the business & is continuing the line, but cost sorta doubled.
Used Plum Brown on my first rifle, but it didn't "bite" as well as the cold browning. It's almost all gone now after only 26 years of shooting.