Fieldmaster S/N?

[600RemGuy]

Up to around '68-9, serial numbers weren't required on 22s. You'll have to date it by the barrel code.

[John Gyde]

[quote="600RemGuy"]Up to around '68-9, serial numbers weren't required on 22s. You'll have to date it by the barrel code.[/quote]
Remington started putting serial #s on all 22s in October 1967. Yours must be before that. As stated above, you can get the month/year of production from the barrel code. Check on main page for instructions.