I finished my comparison of brass 'cleaning' in my Midway vibrator...Pic attached...
All three were 'vibrated' for 8 - 10 hours in the indicated media, with no additives.
(The middle case has a shadow near the base...That case has not yet been resized in the .223 Remington sizing die...It's as-fired...The other two have been .223 resized, and measure .372"/.373", while the fired case measures .385"...It expanded .012" from the sized .223 sized case when fired in my Mauser C96...)
They all turned out acceptably clean, but if I had to choose, I'd say the crushed walnut shells got the cases the cleanest...the insides even look cleaner...
