Thanks for showing and supporting with the data, it's a nice matching K98k!

There is much space, maybe the barrel lot number is hidden under the woodline, it's a 1940 Radom barrel blank, finished at the Steyr-Daimler-Puch Letten factory.
I will copy and paste my comment to make the discussion more understandable. In the other thread with the bnz 40 I have written:
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The "bnz 40" belong to the "660 1940" order/production run. The K98ks with the code "660 1940" and "bnz 40" in the "k" and "l" blocks got assembled in April/May 1941."
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By the way, in 1939 there was no K98k production, the assembly of the first order "660 1939" started in January 1940. By January 27, 1940, a total of 1,440 K98ks had been accepted."
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One of the most important things: The previously assumed 1941 Steyr production numbers are not correct, due to the high number of K98k an error in the old document was assumed but it was a wrong assumption.
Correct is:
In 1941, the K98k production numbers was not lower than in 1940, but higher. The production numbers for 1941 even exceeds the numbers for 1942.
The "Large Font" Steyr receiver with e/623 Waffenamt acceptance and the "Small Font" Radom receiver with e/77 Waffenamt acceptance are a separate assembly run. These two assembly lines at Steyr-Daimler-Puch in Steyr assembled K98k at the same time, but one of the two lines started with the bnz41 first, the other assembly line followed a little later with the bnz41 receivers. These two K98k assembly lines at Steyr were strictly separated from each other, the K98k from the second assembly line even had its own name."
The output of K98k at Steyr is not uniform, in some weeks more was produced than in a whole month just before. Some letter blocks were assembled over a period of more than two months. In other months, more than two complete letter blocks were assembled. Other K98k manufacturers had more consistent production and if you divide the annual production by the months, you can get some usable results. You can't do it with Steyr, the results would be totally useless.
Actually I only said what the Steyr factory documents and the documents from the armaments authorities say. I had to make the effort and analyze all Steyr factory documents. The numbers I used are exact figures from Steyr for weeks and even days.
Your "660 1940" Sn 825k got assembled around mid April 1941. During this period an incredible amount happened at Steyr. A complete second K98k assembly line had to be set up and two different K98k series had to be assembled strictly separated from each other. In addition, a third rifle, the G.29/40, was assembled in the same department during the same period. In addition they was busy with other weapons like MP40, MG34, PzB39, Vis-pistol etc. In the past winter there were many problems due to energy difficulties, transport difficulties due to a lack of wagons was also a problem later on and many other things.
It's not a mistake, your "660 1940" Sn 825k got assembled around April 1941 and some days later "bnz 40" Sn 9724k and the other "bnz 40" coded receivers. Up to the "n" block they are intermingled with the "660 1940" coded receivers. When the order (660 1940) was delivered, the Steyr K98k production was continued with the Steyr "bnz 41" coded receivers. The second assembly line with the "bnz 41" Radom receivers was already in operation when Steyr "660 1940" K98k were still being assembled.