Cleaning corroded lead bullets in cartridges

Does anyone have any good suggestions on the best way to clean corroded lead bullets that are in live cartridges? When I reload I run my loaded rounds through a vibratory polisher with corn-cob media to clean all the lube and grime off the rounds left by the reloading process. This would clean these rounds but not sure if it would diminish the “originality” of the cartridges and decrease their value. Any ides?
Thanks,
Joel