I don't think the KleanBore cloths are abrasive. They seem to soften the lead enough to smear it around and get it off the cylinder and onto the cloth. Using the cloths alone is a long slow process so you may want to listen to those who advise soaking, etc. Once you get it clean, it's a lot easier to keep it clean. IE, don't let it get that bad again.

As someone else said, if the cloth does remove any metal, it may take a decade or so of steady use before you detect any measurable difference.

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