"AD" prefix indicates 1967
Serail number and features
About 1973
That should be 1975
M prefix to serial # = 1952 manufacture. Jim
"AX" prefix indicates 1981
The prefix letter shows the year of manufacture. 1956 is letter S
Harrington & Richardson used the Prefix AT in 1983.
1973
How old is my Topper 88 HARRINGTON AND RICHARDSON GUN serial number
what letter or letters are in front of serial number
serial number suggests a single barrel, hinged frame Model 1908/08 shotgun - if so - 1920-25.
"P" prefix indicates 1953