cleaning brass with stainless pins

[schmidtb2]

the experts say not to use a vibrator tumbler with stainless media pins and water.....what happens when you do? My tumbler has rubber gaskets and should be watertight......but before I buy $50 worth of pins, has anyone tried it......Barry

 

[AR Shooter]

It peened the case mouths when I did so in Tumbler Model B tumbler. I now run the small ceramic and only about 10% of the stainless pins and only for ~1 hour and cases come out clean and shiny and no peening. YMMV.