I'm told the 870 uses a ser# prefix and that prefix will narrow down production to a couple yrs sometimes. Othertimes it's longer stretch.
Remington used to give customers the yr of mgf'r over the phone if you called their 800# and went thru all the automated questions and selections and got thru to the Service Dept.
I don't know if that's is still true or not.
Anyway here's the 870 ser# prefix chart I have . I don't have anything more recent.
The info is common on the net and there may be more updated info around or even some that conflicts this chart.
870 Serial Number Prefixes:
-closest-known year of introduction
(no letter) - 1950
S - 1968
T - 1974
V - 1978
W - 1984
X - 1990
A - 1991
B - 1994
C - 1997
D - 2001
AB - 2005
RS - 2009/2010?
CC - 2017/2018?
