Try the 50/50 distilled white vinegar and hydrogen peroxide to get works ok
I cleaned my comp and then polished it to a mirror finish then soaked it with the Dillon brass polish the lanolin in it
got this from another thread here and I didn’t think it would work but!!
shot 300rds and sprayed it every 100 rds came home and cleaned it
carbon was able to be wiped out with a rag almost no scrubbing!!!