Winchester Carton "K" codes help

I thought we had discussed this before but I can’t find it using the “search” function.

What is the key to the Winchester carton and box “K” codes? I am looking at a couple of pre-war cartons which I believe were manufactured between 1925 and 1938. Codes are:


I believe they mean:

March 7, 1930
March 8, 1933

Am I even close??? What does the “C” mean.




The “K” codes on Winchester boxes are like index numbers…they identify the caliber and load contained within the box.
For instance, .30-40 Krag Silvertip 180 grain is K3050C
Western, for the same load, used K1707C
If anyone knows the significance of the K and C, let us know…

Winchester began using these codes about 1922…


Thanks Randy. So, I guess that means the only way to date the Winchester 1920s thru 1950s boxes is by the use of the “K” product codes (1921 - 1952), the Winchester/Western/Olin company names, and the box colors? After they started using the Western “system” in the mid 1950s it was possible to date the boxes by the box codes.

Is that right?