Bigcountry, so basically this guy is saying that the oil you put over it will not neutralize its(Sweets) corrosive properties. I think this could be possible and I would think it would depend on the quality of the oil used. I have very mixed opinions on the various copper removers having tried them all and prefer not to use them. If I suspect there is that much copper buildup than the Outers Foul out 3 comes into use. Lately I have been trying Montana Xtreme...now if you take the cap off this stuff and take a wiff it will knock you down. The company and suppliers claim it can be left in the bore and will not damage it....I have tried it and it is every bit as effective as the Sweets and the CR-10 but my deweys cleaning rod didn' t melt(like it did with CR-10).