Primer Residue Help
I trying to clean my dad’s Optima and there seems to be more black residue behind the breech plug than I remember. I have tried everything I have, Shooters Choice, Powder Blast, #13 Bore Cleaner, Break Free, Advanced shooters Solvent but nothing seem to work except scraping with a knife. Even a brass brush on a drill does very little. I think this is primer residue. Anybody got any tricks?