Orion2000 had it right... In order to keep my brass separate I found a chemical for blackening brass at my hobby store and I soak the brass for one rifle in this for a few seconds and tumble it. There is no doubt which rifle that brass belongs to.
You can use any of the cold bluing chemicals to blacken brass, but they are fairly expensive. If you Google �blacken it�, you will come up with a chemical used to blacken items for hobbyists. It is also used to antique brass for old house remodelers. There is a similar chemical used to blacken the copper used in stained glass. I find that after a good degreasing of your brass, a quick dip in this stuff and then a rinse in cold water is all that it needs. Then, 15 minutes in the tumbler gives you a darkened, but clean brass that is very easy to separate from another rifle�s bright brass.
