I shoot a lot of lead bullets that is the reason for my soap and water wash as a first step.
Between the residual lube, the greasy soot, and powder residue, even brass which has not hit the ground has a lot of water soluble surface crud
It will come off in the vibratory cleaner, but soon leaves the media greasy. My media used on washed brass lasts much longer. I too keep old dryer sheets and pcs. of shop towel circulating in the vib. c.

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