I purchased a set of Pachmayr Presentation Grips for my Colt Python. Grips come with gold medallions. They look perfect on the outside. But inside on both right and left sides the rubber has turned white. I'm assuming this is some kind of deterioration of the rubber? I've seen this on some older rubber grips. Since this is the side in contact with the metal of the frame, do I have to worry that it will damage my Python's finish where the grips touch metal?