I was thinking of getting a old barrel, and take valve grinding compound to the bore. Scrub that thing back to bare metal. After that clean it all real well. Then take a chop saw and chunk the barrel up and test each individual chunk. I might have a handle on half of a Hawkins barrel. If I get that I will repeat the tests and after seeing how many chunks I can get off it, (2" should be plenty long) I will let the forum pick the powders to be tested... and under what kind of conditions...