I have. I absolutely love it. If you swab a wet patch of the stuff through the bore a few times then let it sit for 15 or so minutes like the instructions say, it seems to clean out everything. I tried it once with only a 5 min or so wait & it did OK but not great. It cut my muzzleloader cleaning time in half, even got the plastic sabot residue. I only use 777 though, not sure what it would do for blackpowder, probably should still scrub w/soapy water. But for every thing else gun-bore related it does fine for me.