Well that's just the thing about XADO. There isn't any actual coating in the barrel. The chemical cleans and hardens the steel, sharpens the rifle grooves, and creates and ultra-smooth, ultra-clean finish leaving nothing behind. The chemicals actually react with the steel and form a highly polished, hard, ceramic finish. I talked to a guy who uses XADO on engine parts and is amazed at the performance increase due to friction reduction.