It's not really a scratch, it's a rub mark. The S&W design has the end of the extractor rod spring-loaded to extend out of the extractor star. It forms the rear lock for the cylinder, when you push the cylinder release latch forward, the extractor rod is forced into the cylinder; out of the frame and pushing the forward locking lug out of the front of the extractor rod housing, allowing the cylinder to swing out. But the since the extractor rod is spring loaded to extend out of the extrator star, it rubs against the frame as the cylinder is swung out. There is nothing anyone can do to prevent this from happening on a S&W.
The old Colt design (Python, Detective Special, Officers Model etc, not the Mk III, Mk V or Anaconda) works differently. The cylinder release latch controls a pin the sticks out of the frame into the extractor star. You push the release latch away from the cylinder, retracting the pin and allowing the cylinder to swing out of the frame; without putting a rub mark on the frame. There also isn't a forward locking point in this design, which is why the old Colt design's extractor rod just hang under the barrel instead of fitting into a forward locking lug like a S&W.
As far as the lines around the cylinders, they are caused by the cylinder bolt scrapping across the surface of the cylinder. This can be a result of incorrect timing, or just careless handling. If you close the cylinder so the bolt fits neatly into the bolt cut, then you won't get this line on a well timed revolver. If you close the cylinder so that you have to rotate the cylinder after it's in the frame to get the cylinder bolt into the bolt cut, the cylinder bolt scrapes around the cylinder leaving this line even on a well timed revolver.
