Shiny brass -- it may not shoot more accurately, but it does make you feel better about your hand-loaded ammo. While it's not necessary to get brass bright and shiny after every firing, it is a good idea to clean powder residue, grime, and grit off your brass before you run cases into sizing dies. There are many ways to clean cartridge cases.
UltraSonic Case Cleaning
Test: Case polishing and cleaning methods with the Hornady M-1 and
Ultrasonic Cleaning Once-Fired Brass - Tovatech
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Better Ultrasonic Cleaner
Buy Rotary Case Cleaner and More
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