Bore-a-New cleans lead and fouling out of the barrel. Use once or twice a year, after lots of shooting. Swab Bore-A-New in the bore with a good coat over the barrel, let it set 8-12 hours, usually overnight. Then clean with a solvent such as Hoppes 9 (not Hoppes 9 Plus) or Shooter's Choice. Heavy deposits of lead and fouling retreat. 1.5 oz.