Sorry to be coming into this conversation so late, but I may be able to help. I just recently completed this same project on my Rem 798 in .308. Brownells no longer sells their action polishing tool, you can see how it was used in a Midway USA video titled "gunsmithing- how to polish the bolt lug raceway on a Mauser bolt action rifle". I fabricated a tool of my own that worked quite well using a piece of 3/8" steel rod(10"), a chunk of oak for a handle, and a piece of 4140 steel(.375x1x2.25 inches). I'll attach a picture. Took me about 5 sheets of sandpaper from 320 to 900 grit but she is SLICK now. Just be careful not to polish the backs of your bolt lugs obviously.