Just a FWIW.... I tumble my resized rifle cases to remove the lubrication. Using my older style corn cob media I found primer holes clogged in over 50% of the cases. Now that's no big thing when doing 50 cases or so, but I do hundreds, so it's no fun. Then I found a tip on another board; Harbor Freight Walnut Shells - Fine -24 Grit..... no more clogs!
BTW, interesting posting on that same thread. A long time benchrest shooter did a test using cases with and without tumbling media clogged primer holes; same load; no noticeable difference in velocity or group size!!! Wow, I didn't expect that result! Still, why chance it, so I'm glad to find something that eliminated the problem!
Thanks!