For $500, who cares whether it's a first or second change target? Just buy it!

Ralph is correct: locator dowels for the ejector star absent -- first change; locator dowels present -- second change.

There is some interesting additional stuff down inside, but you'd have to take the gun apart to see it. For example, the first change has a keyway milled in the frame and a boss on the rear face of the trigger rebound slide to restrict its possible travel range. Absolutely unnecessary. In the second change production the keyway and boss were left out.

Quite possibly there were guns produced that had both the rebound slide keyway and the dowels in the cylinder, or lacked both those features. I have no idea how those guns would be designated. (Maybe first and a half change, varieties A and B?) But it is clear that over a fairly large range of serial numbers the guns we call first changes and second changes were produced side by side.

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David Wilson