Your serial number indicates that your Glenfield model 20 bolt action was made in the year 1980.
1978.
THIS Glenfield MOD 50 BOLT ACTION SHOTGUN WAS MANUFACTURED 1966-1972. I HAVE ONE AND ALSO CANNOT LOCATE THE SERIAL NUMBER.
Glenfield,which was made by Marlin Firearms Company made a bolt action .410ga shotgun from 1956-1965.This was the marlin model 59 which is the same shotgun as your Glenfield model 60.
$100
write to marlin with any and all writngs/markings on reciever/barrel and serial numbers
Inexpensive .22LR single-shot bolt-action sold through mass-marketers. Your gun was made in 1975.
1981. $100 tops.
1932-1957
$25 to $125, depending on model and CONDITION.
It would have to be older than the implementation of the Gun Control Act of 1968, which mandated that all cartridge firearms have a serial number.
I paid 97.42 with tax and everything at my local pawn shop Friday the 13 July 2012