I’d try soaking it with solvent or penetrating oil and giving it a good scrubbing with a bronze bore brush. We want to remove dirt and grime, not metal. Polishing compound will remove metal. Once it is clean you can assess and plan your next step.

Mike

If your 1875 Tool has any condition to it, I’d be very careful, as the original gold paint finish can very easily be stripped off. If there is not much of the original paint finish on it, I wouldn’t be too worried but would not use anything mechanical on the tool. These are Cast Iron and not steel. Easily damaged which is why I’d only use some good hand pressure and elbow grease with a light gun oil on some real fine steel wool. Take it easy and it’ll do fine.

These old tools are good for making up a few rounds but if you planning on doing some serious reloading. You would be better off get a Lyman or RCBS bench reloader.

Sincerely,

Maverick