There is some confusion about how Marlin Firearms used their serial numbers to ID the year of manufacture.
Some people are under the belief that all one has to do is �subtract the first two digits of the serial number from 2000 and that is the year of manufacture�. This is only partially true.
In order to find the year of manufacture one needs to know the *first two character�s* as a minimum, either letters, numbers, or a letter number combination on the firearm. In addition to the first two characters of the serial number it�s also imperative in many cases to know the model number.
The serial number depending on the model of rifle, will be located either on the upper or lower stock tang, or side of the receiver.
Below are the manufacturing date codes. Please note this list is NOT INCLUSIVE of all Marlin firearms. Only those manufactured from 1941 through 2011 which have serial numbers on them.
EXAMPLES:
If your rifle has the single letter �V� serial number prefix, that indicates a 1962 year of manufacture.
Letters �AC� = 1967
Numbers �24� = 1976.
(Notice there are no �I�, �O�, or �Q� serial number prefixes in use. Too confusing with the number 1, and 0 - zero)
LETTER/NUMBER PREFIX DATE OF MANUFACTURE
B 1941
�
No commercial manufacture due to WWII production / retooling from sometime in 1941/42 until 1945
C 1945
c (not capital C) 1946
D 1947
E 1948
F 1949
G 1950
H 1951
J 1952
K 1953
L 1954
M 1955
N 1956
P 1957
R 1958
S 1959
T 1960
U 1961
V 1962
W 1963
Y 1964
Z 1964
AA 1965
AB 1966
AC 1967
AD EARLY 1968
68 LATE 1968
69 1969
70 1970
71 1971
72 1972
27 1973
26 1974
25 1975
24 1976
23 1977
22 1978
21 1979
20 1980
19 1981
18 1982
17 1983
16 1984
15 1985
14 1986
13 1987
12 1988
11 1989
10 1990
09 1991
08 1992
07 1993
06 1994
05 1995
04 1996
03 1997
02 1998
01 1999
00 2000
99 2001
98 2002
97 2003
96 2004
95 2005
94 2006
93 2007
92 2008
91 2009
90 2010
89 / MR (See note Below) 2011
Sometime in 2011 the serial number prefix became MR. This was done in conjunction with the sale of Marlin, and subsequent move to the Remington plant in Ilion, NY. Speculation is that once receivers started being manufactured at the Ilion plant the prefix became MR.
*While potentially not relevant to this specific thread. As of late 2013, a Marlin .22 RF rifle (XT-22 Mag) had a serial number prefix of MM reported and verified. It is unknown as of December 2013 how Marlin (�Remlin�) will continue with their serial numbering convention.
Also while not specifically relevant to the model 336�s. It is important to note that some �budget� Marlin Rimfire rifles that were manufactured prior to 1968 did not have a serial number. These had letter �codes� on them that will help ID date of manufacture. See here for these guns.
http://guncollectionsonline.com/marlinmodel60.htmAll model 336�s, and all other models of centerfire lever action rifles produced by Marlin, as well as lever action rimfire rifles (39/39A, etc) made by them will have serial numbers.
Until 1968, long guns sold in the USA were not required to have serial numbers on them. After 1968 all firearms manufactured or imported into the USA were required under US Federal law to have serial numbers on them.
Hope that helps some folks.