pics of the areas of concern would help.
Sorry, I wish I had a digital camera.

When I open the cylinder and look inside the chambers from the front, I can see a small dark ring maybe 1cm deep from the face. The ring itself is maybe 1mm wide and present in all 5 chambers (i.e. 5 small rings, one in each chamber).
51 rounds were fired from this gun so far, a .357 at the factory, and 50 .38 Special Winchester 130 grain full metal jacket rounds.
By face of the cylinder I mean the front: http://www.geocities.com/kemays/rev_cleanface.jpg