Not sure what type of ceramic that is. Is it harder than the steel die? If it leaves a residue on the brass, there is dust, just not visible and an unknown quantity. That stuff in the lungs is a bad thing. Primers still in the brass will contaminate the media with lead salts, which is a major source of lead exposure. I would investigate very carefully.
Interesting. I`ll look into this a bit more.
Did the 1/8 clean the small primer pockets?
Not sure what type of ceramic that is. Is it harder than the steel die? If it leaves a residue on the brass, there is dust, just not visible and an unknown quantity. That stuff in the lungs is a bad thing. Primers still in the brass will contaminate the media with lead salts, which is a major source of lead exposure. I would investigate very carefully.