Sorry, I did not see this.
All I do is wipe them off with the towel I have on the bench That is part of my bench set up.
One item of note. When I do a barrel, I do absolutely nothing to the chamber after reaming. I have found through experience that the finish the reamer leaves is just right for the correct amount of “grip” that the case walls have against the chamber combined with ease of extraction.
Although a polished chamber might look pretty, I believe that polishing chambers is counterproductive to how the case interacts with the chamber at peak pressure.
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