If its really a K72,000s gun, then all the tables will tell you 1948. I've become a real skeptic (based on letters), so I'll hedge my bet and tell you either 1948 or 1949. The only way to tell is to spend the $50 and get your factory letter. Unless its really important to you, as in the gun has known family or historical significance, its probably a waste of money. Late 1940s gets you pretty close. My experience in lettering post war K22s is kind of unhappy. All you normally get is the name of a distributor, with a very occasional hardware or sporting goods store. If you bought it or inherited it and have reason to believe its been in your locale for a long time, it might be worth while.
The old truth, that the letter adds as much to the guns value as it costs doesn't seem to be true for most postwar guns. The exception being one with rare or unusual features. Of course, its your money.
