Wet tumbling brass strikes me as the most efficient way to retrieve their original brilliance. Lyman’s Cyclone wet tumbler with stainless pins in cleaning solution gave me dazzling results in less than an hour.
Lyman Cyclone Rotary Tumbler Stainless Steel Case Tumbler
Lyman Products Cyclone Brass Case Dryer 115VT, Gunsmithing Tools - Canada
Wet Tumbling Brass with the Lyman Cyclone - The Armory Life
Lyman 7631550 Cyclone Rotary Tumbler 115V,Multi : Sports & Outdoors
Stick with dry media or wet tumbler
Lyman Cyclone wet tumbler for brass
Hornady Rotary Case Tumbler, Reloading: Creedmoor Sports Inc., Brass Tumbler
Lyman Cyclone Rotary Case Tumbler
Lyman Cyclone Stainless Steel Rotary Case Tumbler: From Unboxing to Wet Tumbling Brass – Ultimate Reloader
What do I need to start wet tumbling? : r/reloading