banjodave:  Dang that's a beautiful 1898 Krag.  The 'cartouch' stamp in the wood is the inspection acceptance (into service) mark.  "J.S. Adams  1900".  I would wipe the light surface rust with soft flannel cloth saturated with Hoppe's #9 Nitro-powder solvent.  This is a deep penetrating oil and often does the trick on light surface rust.  I would be reluctant on this pristine rifle to use anything more abrasive.  I would protect the metal with RIG (rust inhibiting grease) applied with a lamb's wool RIG pad.