WHAT DOES CCI 209 MAGNUM PRIMERS IN STOCK MEAN?

I bought a plain optima, not an elite, about 6-7yrs in the past. I tried many various makes of primers in it. I could about six rounds from the standard CCIs or Earn magnums after which you can the primers would get packed in with carbon. They ended up very hard to extract! With most other brands two-three pictures would have to have tools to recei