Use Hoppe's Foaming Bore Cleaner to dissolve and remove copper and powder residue quickly and effortlessly. The easy dispense tube makes it easy to dispense into the bore and the superior cleaning formula does the work for you, so no brushing of the bore is necessary. The orange foam also includes a color change effectiveness indicator and will turn blue, indicating copper removal, or black, indicating powder removal. That way, you always know when it's working.