RCBS make 2 one like the Midway/frankford and a hexagonal one the runs on wheels on a base, that one is noisy whatever you do, the vibratory one is the same really as the other two. Midway/frankford is same machine different colored drum, I hae two and they are fine, the Midway is ten yrs old still going, the frankford 2 yrs and fine. I fill 2 thrds full with corn cob and add a half packet of the RCBS polish powder, ( which works better than anything else ive tried and doesnt harm the brass) the other has walnut in and a little polish powder for final finishing. I just dont pile cases in until there is no room left, but put reasonable number in like 100-150 rifle cases and leave it for a couple of hours , then move them over to the walnut media for the same time, they come out like shiny gold. Hornady and Lyman make bigger ones if you want to polish a lot of handgun cases at once.
I dont leave the lid off because you quickly lose the polish out of them as dust and it cannot be good for the lungs either. You can see the difference, if you put cases in and it doesnt rotate media and cases , just trickle in a bit more polish powder and it immediately starts to rotate everything round properly, when it starts to not polish so quick do the same again. that way a packet lasts for ages. the liquid stuff just makes a mess and doesnt work as well in my experience, plus my cases arfe dry and a dustoff with a little compressed air or a vacuum and they are ready to load. All the car restorer compounds contain ammonia which weakens the brass and shouldn't be used on cases anytime. IMHO
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