I have used the reloder 15 in 4 different calibers. What I refer to is after I get get the barrel clean with many patches and Hoppes number 9 and or a good copper cleaner if I see streaks, not often. I will run a bronze brush down the bore (not after I use copper cleaner) and then run a patch with Hoppes number 9 and it comes out black. That is what I refer to as powder residue, What else could cause a black patch but powder. Some of you may want to try this yourself. Run a bronze brush down the barrel a couple of times and then run a clean patch with hoppes or even gun oil and see if it comes out black.
