bullseye: My credentials aren't as impressive as Mr. McMillan's, but I do have some experience with new factory barrels and used ones that have been neglected or abused by previous owners. Factory barrels aren't lapped or polished as a rule; the first couple of hundred shots through therefore, apparently serve to 'season' the bore, wearing away microscopic imperfections. Especially during this time, firing too many rounds too fast is not a good practice. I try to keep the barrel cool, especially until a few hundred shots have gone down the bore. That means that at least at first, I shoot only a few shots per session, and of course cleaning after each session. It's not so much the cleaning that helps is the gradual wearing in. I have used JB Paste for years on neglected barrels, to scour out years of fouling there was nothing better until the electric de-re-unplaters came along. Maybe JB isn't good for fine lapped bores. All I know is that it is a rejuvenator and accuracy restorer on neglected barrels of the ordinary kind. As for chrome plated bores I have little experience with them, and can make no recommendation. slabsides
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