Tumbler Media? which is best?

[Rantastic]

Im going to be doing brass rifle cases... lots of them and want the best polish in a hurry.... what does everyone use and how do they like it? I have already heard from some people than corn cob media takes twice as long as Walnut, so what combinations would you reccommend?

[Huntnut]

I tumble them first in walnut before I resize them then I use the red Lymans stuff after resizing-makes them look better then new.

[Mike_W]

I use green cob 30-45 min and its nice and shiny I also have added the lyman brass polish to the media