I shoot corrosive 1989 Czech 7.62X54R in my Nagants. First thing I do when I get home is run a couple patches soaked with either nitro-solvent, black powder cleaner or ammonia. I'm not suggesting this, but I had a friend who went hunting with his, after the range where he fired alomst 25 corrosive rounds back to back. He was in the bush and forgot his kit, so he pulled a "Grandpa" move and used *ahem* "Uric Acid" to flush the barrel, an a long twig with some spare cloth to sweep it.