brass tumbling

[fred666]

can you tumble brass that has been newly primed?

[Eric Marleau]

I wouldn't.

Eric

[LarryFlew]

better after loaded than just primed in case your polish and/or media mess up the primer.

[Seismic Sam]

I also would NOT, for the above reasons, and that fact that if you tumble unprimed brass, on a few percent of the cases there is a piece of media jammed into the hole that requires a dental pick to remove. If you obstruct the flash hole really good with a piece of media with a primed case, there's no telling what will happen. Probably nothing, but maybe a squib load that runs the bullet two inches up the bore, cycles the gun, and sets you up for a KABOOM on the next shot.

And if that isn't enough, IF you check all your brass after tumbling and find some of these, you get to try and dig the media out of there right on top of a LIVE primer. There ain't no happy ending here at all...

[870TC]

I've done it before, with dry media -no polishing compound added. Would not hesitate to do it again. I did it because I bought some new primed brass that had gotten tarnished. Some granules of media did stick in the flash holes, it shoots out fine no problems. That being said, there was a big post about this over on cast boolits a few years ago, some of the guys over there tested the "plugged" flash hole brass for accuracy, they found (rifle) groups opened slightly. Not enough to bother with hunting accuracy but would make a difference for scored targets.