Had my hands on a model 58 today but it looked too nice. Seemed like a high polish blue. Removed the non original rubber grips and found a R-S and the date 6 79. Also there was A4 stamped twice on the grip frame. The gun numbers to 1973. It was super tight and had no visible wear. Any idea what these markings mean? Another thing I noticed was the smooth trigger. My SCSW version 1 says this is correct but the later SCSW says it should have a serrated trigger? Any help would be great.
Thanks.
BTW the asking price was $700. Not great but don't see them often.

Is the serial number also stamped on the cylinder and/or flat under the barrel?

IMO, the R-S and the 6 79 confirms a refinish June 1979.
I think A4 is a assembly/ inspection mark from the get-go.
Price seems a little high.

FYI - a real nice, clean, original one just sold in the classifieds for $800 and it had box.

Wow, you guys are fast. The serial number is on the bottom of the frame. Forgot to look under the barrel. Will get back and look it over better this weekend but think I'll pass. Looked like the hammer was dragging a little on the side plate too. Thanks for the help.

Harryo,

Fact, not opinion, the R-S stamp designates Re-finish Standard (Blue) and is a factory re-finish mark. The 6 79 is a factory re-work date code, June 1979. It would be unusual for these to not be from the same visit.

The marks must have changed later on, my factory refinished Model 28 just has an "R" in a circle stamped on the left side of the grip frame.

When I saw a date I figured it must have been for rework. Some older guns I have are marked with a star for a rework sign. This site has been a huge help in making educated purchases. Thanks again. Saved me some $$$.

Whether the gun is re-finished or not the circled R is an inspectors stamp, not a re-finish mark. Re-finish marks include the finish to be applied (they are stamped before finishing, not after) and have some form of R-S, R-B, R-N by themselves, in a rectangle, a round-cornered rectangle or a diamond. They are sometimes seen as just the letters. Without the second letter the finish job would have no idea what to apply to the gun.

Harryo,

The date code and star are not mutually exclusive. The star is an external mark to indicate the gun has been re-worked in some way, at some time. The date code is internal and gives specific information as to when the work was done. You can have a gun with just a date, or date and the star, but, theoretically, never a star without a date.