Polishing rails on M98 action?

I had my M98 built finally. It is now a fine shooting 7mm magnum. However when I got the gun back, cerakote and all, the action which used to be slick as anything, is now gritty and tends to lose momentum right before the case hits the ejector. Ive been able to work through it, but now, 100 rounds in or so, I would really like to smooth it back up. Is there a best practice on how to polish the rails back up? Any help would be appreciated.

Thank you!