If your brass is not too dirty, the big advantage of cleaning (however you do it) after sizing and decapping is that it removes the lube used to size. This needs to be removed before the ammo is used. Depends on the lube you use if this is an extra step. Lots of lubes can just be wiped off in the final check of the ammo, that is what I do most of the time. Brass needs to be inspected after tumbling, among other things to insure all the media is removed. This should catch any media in the primer pocket. If you use a progressive, obviously you must clean and lube before then remove the lube (if it was required - not needed for carbide dies) after you have finished.

Clearwater,

Reaming primer pockets is required on military brass with crimped primers, but probably not be used all the time. I do it on new brass then rarely after that since it often removes some brass and can, over time, loosen the primer pockets.

Respectfully,

Jerry