Re: Walnut and comet cleanser in tumbler
Be careful about using anything other than walnut shells and corn cob media for cleaning brass.
Some chemicals not made for cleaning or polishing brass pistol and rifle cartridge cases may contain a chemical that attacks the strength of the brass case. It is not a good idea to be fooling around with chemical on brass cases that may be required to contain up to 65,000 psi of pressure. Every bit of strength in the cases is necessary!
Also since the cases are heat treated to make them strong where they need to be strong, using any heat on them is also a no-no, especially in the head of the case.
These points are safety issues.
Stains from firing on brass cases in no way effects their function. Brightly polished cases are for bragging rights and do nothing to promote accuracy or shooting skills. Cases only need to be clean enough so that no residue is left on the outside of the case that might scratch the reloading dies.