(A lot of my text here is a re-tread, I'm bored & tired of waiting for my 4 5/8. I did change ending in 2s to 1s...)
I realize this is oversimplified w/o hard #'s, but it should be somewhere in the 'hood, ballparked. 16831-17331 is 500 units/ one quarter production for both lengths combined.
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As well, I started w/16831 coz that was the earliest SN posted that I found. I've seen 17233, 5.5", and that's right @ 100 from the end of the first quarter, for both pistolas combined
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chet15 sez:
"520-17482 would indicate that at least 600 Specials have at least had their frames serial numbered, but who knows when the rest of those will go through the final "process".
The earliest Special now stands at 520-16831, a 4-5/8"