Nope.
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<br>You're getting the bore clean as a whistle so the bullet does the ironing. If you leave the fouling in, then the bore surface will not be exposed to the bullet ... the fouling will act to "protect" the bore surface from further polishing/burnishing/ironing. But if you keep shooting a bullet through a squeaky clean bore, the bullet will iron out the bore's imperfections to a degree. Once that happens, the bore will foul less, and many times shoot better.
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<br>That's a dumb guy's understanding of the concept. Hope I didn't make more of a fool of myself than already widely assumed.
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<br>Rick