I use Laurel Mountain Forge browning solution- which is pretty easy to use no matter what you do BUT. My first few guns I took down to 600 grit paper. The rust "took" in spots but after a few coats the spots all blended together. Some one told me to only go to #320, which I did on maybe the next two guns. Better, faster. This time I only went to #220. I could see the lines of the paper but I waited about 8 hours between coats which built up a heavy coat and darn if I can see any lines. Rather than "old penny" smooth it is a little rougher but I think it looks pretty good and it sure was quick and easy. In any event, IMHO if you are getting spots or streaks when you brown, think about preparing the barrel with a slightly rougher sand paper- I think it encourages faster, more even browning. I may settle on #320 but as I said even the #220 looks good.