Savage firearms made between 1949 and 1969 were marked with a coded Date Stamp indicating year of production. This stamp consists of a single digit number and a letter inside of a circle with the letter indicating year of production. The below chart indicates what letter corresponds to what year. Not that the letters "O" and "Q" were skipped.

1949 A 1960 L
1950 B 1961 M
1951 C 1962 N
1952 D 1963 P
1953 E 1964 R
1954 F 1965 S
1955 G 1966 T
1956 H 1967 U
1957 I 1968 V
1958 J 1969 W
1959 K

On Model 99's this date code stamp will be on the bottom of the lever boss just ahead of the lever pivot pin as shown in this photo.
(photo courtesy of forum member Moriseb)

Click image for larger version. 

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