I've Always Been A Bit Apprehensive About Case Polishing. My Fear Is Based On The Fact That You're Removing A Tiny Layer Of Brass From All Surfaces Of The Case Every Time You Tumble It In A Granular Medium. With The Case Thusly Getting Progressively-Thinner Each Time You Polish It You're Constantly Weakening It Ever-So-Slightly.
I find it very hard to belive that tumbling brass would reduce enough material to ever make a differance. My 218 BEE brass is about .008-.009" thick at the case mouth. I have shot it several times and tumbled it several times and I see no ill effect on case wall thickness or reduced neck tension from deminished brass. I have seen the brass work hardened to the point of neck splits, but that is another topic all together.
The Ideal Exercise Here Would Be To Resize,Load,Fire,& Generously-Tumble A Batch Of Cases (Say For Instance)5-10 Times And Employ A High-End Digital Micrometer(Before & After) To Gauge Each Of The Mouths And Determine If They've Shed-Off Enough To Be A Cause For Concern.
"Tigger" Just Reminded Us In The "Crimping" Thread That We Also Have To Consider The Gradual Stretching Of Cases That's Caused By Repeated-Firing And Resizing. This Will Naturally Thin-Out The Case Walls Very Slightly And It Seems To Me That Both Factors Combined Could Have A Most Undesirable Effect.
P.S.
Wooden Shaft Q-Tips Work Beautifully For Swabbing-Out Primer Pockets* * *
Last edited by J. E. Markel; 10/09/2009 6:09 PM.
