I use NuFinish also. My "typical" is to viberate about 50-75 pieces of rifle brass at a time.
I get her going and dump in the NuFinish. Five minutes later I put in the brass. It is always mixed brass. Some 45-70 and 444Marlin size,some 300BLK size.
My media is walnut because I get it free. I have a buddy that wet tumbles but I consider that a PITA. --- SAWMAN