Hi-Wall56 wrote on Feb 16^th, 2015 at 10:19pm:


After a lot of testing with ceramic media and stainless pins in a tumbler I'm convinced one can never completely eliminate peening, only reduce or minimize it.  And stainless pins tend to be worse than ceramic concerning peening.  If, after cleaning, take a very sharp pointed tool and slide it up from inside and outside of the case to the mouth.  If it catches, even slightly, at the case lip then peening is taking place.  For more details on my testing and results, see my article on the following link.

(You need to Login or Register to view media files and links)

BTW, one of the big advantages of stainless is it can be used to completely clean (including the primer pockets) any size case, .50 caliber down to as small as .380 Auto, possible smaller.  So I use ceramic media to minimize peening with the larger cases and switch to pins when the caliber gets down to around .38 or smaller.

Wayne

I wonder if it makes a difference whether your Thumler has the high speed motor or the low speed version?

Mine has the lower speed, and peening doesn't seem to be a problem.

Intuitively, it would seem that the slower speed would produce a less violent impact on the cases as they tumble.

Paul

SSShooter wrote on Mar 11^th, 2015 at 9:50am:


I did not test the small Maurer media with larger brass.
I used about 100 pieces of 22-250 with approx. 4 0z. of media, one cap full of Maurer cleaner and about 2 cups of water (did not quite cover the brass). It cleaned the primer pockets as clean as the larger media. It didn't make the inside as shiny though..............

corn has always worked best for me in a vibrator tumbler, and lasts the longest.

but since getting a rebel 17, that's all i use - s/s pins, water, and a bit of lemishine.