Hi Moose...
I first got interested in polishing when I bought some fired brass from a bulk supplier, and the cases looked like they were buffed on a jeweler's wheel, and then gold plated.
I loved the look, and tried to get mine to look like that, to no avail
I was using an RCBS drum tumbler, and, like your's, it also wouldn't get the brass great looking, even if I left it in for 3 days
It took a while, but now I have it down pat...
I got rid of the RCBS tumbler to a fellow that wants to do moly coating, and got a large Dillon vibratory polisher.
OK... if it's bulk brass from range pick-ups, I wash it in liquid Tide to get the loose dirt and bugs out. Then I dry it
After it's dry... or if it's my own fired brass... I neck or FL size, and deprime using RCBS-2 (water soluable lube). Then I rinse it in hot water, and give it a 5 minute soak in Iosso brass cleaner that is half the strength they recommend.
Then I rinse it, and dry it with a hair drier, or if it's a lot of brass, I lay it out on a towel in the sun.
Walnut shells will remove heavy corrosion, but won't polish, EVER. It is too course, and too hard.
Then I put the brass in the Dillon polisher. I use fine corn-cob... with either Dillon polish, or Midway polish... both are good... and run the tumbler over night, about 8 hours. In the morning, the cases look like they have been buffed on a wheel, and then gold plated.
If the cases are really scratched up, because they are bulk range pick-ups, I will use corn cob, and a mix of half Dillon polish, and Iosso case polish (not the earlier mentioned cleaner).... the Iosso polish has a mild abrasive in it, and will remove the scratches... BUT, you should wash these cases again in Tide to remove the abrasive dust, then polish them in the normal mix again. This scratch removal step only has to be done the first time on beat-up cases.
After that, just polish in corn cob and Dillon or Midway polish.
Now all the cases look buffed and gold plated.
This might be a bit of work... but I do 3 to 4000 pistol case at a time, and last winter I did 2,500 50BMG cases, and (for me) it's worth the work... I love the look of the cases. They really look better than new brass.
CatShooter.
