CWFRITZ, I browned a .45 Kentucky kit rifle about 30 years ago using Birchwood Casey Plum Brown, and it still looks good today and has a rich brown tone, also about 7-8 years ago I did an original Springfield TD at the insistence of a friend (his gun). Both came out very nice.
However, the Kentucky I used the big oven in our county jail to heat the barrel uniformily (your tax dollars at work) and it really came out nice, but being politically correct I used a propane torch to do the Springfield, and it came out ok, but not quite as nice as the Kentucky, my friend was very happy. The main secret, as was stated earlier, is to heat the barrel until the browning solution just sizzles then apply the solution with a small 100o/o cotton cloth (not cotton swabs or cotton balls) in even uniform strokes. Let the barrel cool naturally, then use #4 steel wool and lightly polish off the excess. Let stand for a few hours and if it has the color you want use a light gun oil not WD40, or a cleaning oil, and continue to keep oiled for a few days. Also make sure all the oil is off the barrel before you start and naturally wear clean cotton gloves, have about 3 pair on hand, they only cost about a buck a pair.. Good luck RR:D