Did my M700 match rifle years ago and started with a small sanding drum on the dremel to get the tooling marks out, then a fine stone, then a Cratex wheel, and finally Flitz on a cloth bobbin. Came out beautifully with a mirror finish. Just like any polishing operation you start with the roughest grit first and go progressively finer. Can be done without the power tool but will take significantly longer if there are any tool marks to remove, which there usually are.
