I just do a lot of this

I don't claim to be an expert, but I've been doing this stuff for a long time.

You don't need to tumble for 2 days. I rarely tumble for more than an hour or two. I use fine ground Walnut hulls, with one of a variety of polishing additives, usually ones having Iron Oxide in them. I usually tumble before sizing to get dirt off, and if I'm using a Steel die I tumble after sizing to get lubricant off and clean out the primer pocket.

Don't worry about the blackening inside the case. You'd probably have to use abrasives much more aggressive than you are using now to remove it. Combustion chamber darkening probably does theoretically have some minor effect on the combustion in the case during the next firing, resulting in marginally more energy being transferred to the case in the form of heat, and marginally lower gas temperatures, resulting in loss of a couple feet per second. It's not enough to worry about. Increases in neck tension from being expanded on firing, sized down, then expanded again during loading, have much larger effects.

 

I can't speak for a rock tumbler as I use a Lyman turbo 1200. My media is a 3 to 1 mix of walnut (Lizard Litter from Petsmart) and corncob (bought a bag from MIdway USA) I added a tbl of liquid car polish to this.

I typically set the appliance tumbler for a few hours (3-5) turn it on, close the door and let 'er go. Nice and clean shiny cases come out. Tumbling for an hour or two gets the cases clean, just not as shiny as I 'like'.

 

Thanks to both of you as that answers my question. I need to got to Petsmart for cat food, so I'll get some Lizzard Litter while I'm there.

 

FYI from an oldtimer.

Back in the days before we had the modern tumblers some reloaders used rock tumblers. I recall they were not as efficient and had to run longer to get good results. Two days sounds excessive, but a few hours might not do the job in a rock tumbler.

Tim, perhaps a trial-and-error experiment would be useful.

 

Insulation Tim, I always use something long enough and narrow to run inside the case as media will sometimes hang inside the case. I just stick it in the case and run around the inside all the way in to the head. I also knock any residue out of the flash hole while I'm at it. Just another tip for better detination. Remove the burr inside the flash hole, all brass new and once fired will have a burr. The flash hole is made by a punch creating this burr in manufacturing. They make a tool to remove it. You will get more uniform detination of the powder with the burr gone. I use treated corncob media made by Frankford Arsenal and buy it from Midway. The granuals are smaller than say Lyman so they don't hang as bad as larger particles. Walnut is much smaller but I find corncob to do a quicker job.

 

This is the best deal I've found so far, its a little dusty but throw in a dryer sheet for an hour and your good to go, 25lbs should last you a looong time too.

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92155