@ 1971
K130218 was produced in 1951
I can say that the Winchester model 1400 MK II was made during 1968-1973,hope this helps.
@ 1976
You will have to call S&W to find out.
You can't tell the model number by this serial number.
@1976.
Impossible to answer without the serial number.
what year is yamaha serial nimber 487 000979
Call S&W and they will tell you.
Call S&W and they can tell you when it left the factory
Can't be answered without a DETAILED descripiton of ALL markings.
You will have to call S&W