Re: who knows remington date codes?
I can see your problem. D is September, but there is no XM. X is 1929, 1973 or 2003. M is 1921, 1965 or 1992. There are some double -letter codes, but they are all the same letter - MM, NN, RR, XX, etc. The only thing that makes sense is that you have mis-read the code.
How about a picture of it? Maybe we can do better.
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