IF it HAS a serial number, it will be stamped on the receiver (frame) usually on the left side (as you are holding the shotgun).
However, serial numbers were not required by law on shotguns and rifles until the 1968 Gun Control Act. Prior to that most low cost firearms were not sequentially numbered, due to the cost to the maker. It is not illegal to own a firearm without a serial number, but it IS illegal to remove a serial number, or possess a gun whose serial number has been removed.
"P" prefix indicates 1953
1973
How old is my Topper 88 HARRINGTON AND RICHARDSON GUN serial number
Harrington & Richardson used the Prefix AT in 1983.
1987
"AY" serial prefix = 1982.
1971
1980
M prefix to serial # = 1952 manufacture. Jim
The value of a Harrington and Richardson 7mm Remington mag serial number 52897 depends on its condition. This gun in excellent condition is valued between 125.00 and 200.00 as of 2014.
No way to value with just the serial number and no other details
No way to value with just the serial number and no other details