Had a wild hair today. Have been cleaning lots of 308 brass in tumbler. Some of this stuff is old and has that oily dirty feel. I threw a cartridge in some Muratic Acid. We clean Hastolloy and Siliconized brass with the acid. It cleaned it quick inside and out. For you chemistry majors, could this be an acceptable method to clean dirty brass? Any Chem problems with acid and brass? Finnish it off with tumble to polish.