Have always used crushed corn cobb as my tumbler media. Very pleased thus far with the results. Heard that crushed walnut was the best so I bought some Lymans "Tufnut". The container says it is treated with rouge. Tumbled a couple hundered 223 cases for twelve hours. Used a generous amount of Dillan rapid polish 290. The results were dissappointing. The cases were dull in appearance. Does anyone know if these results are typical. Also is appears as though the flash holes on many cases are clogged with media particals.