Hi Bill, Jan Still (Third Reich Lugers) thinks some of these out-of-sequence pistols were made from leftover parts at the end of the 1942 production. He shows a 1940, S/42 (S/N 4178k), a 1940 byf (S/N 7) and a 42, Code 42 (S/N 9231a). From these few examples and the serial numbers provided, it's difficult to make many conclusions. Knowing the serial number range for each of these would lead to these conclusions, based on the serial number alone. The K-Block could have been completed either toward the end of either the 1940 or 1942 production. The other two were likely completed during the transition between the 1941 and 1942 production runs.
As far as their collectability, I would say to each his (or her) own. As far as I am concerned, it doesn't fit in my area of interest. Some years ago I passed one up and haven't had any regrets about doing it.
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