How many pounds does your rotary tumbler hold? Mine holds 15 lbs, I use a gallon of water 5#'s of stainless steel pins a little dish soap and a little Lemishine and @ 2 lb's of brass. Brass comes out clean and shines like new. Makes it a lot easier to find your brass at the range. I de-prime first so the primer pockets are clean as well.
The media can be purchased at: Stainless Steel Reloading Supplies | Tumblers, Separators, Media, Brass & More!