Dating a 340B in 22 Hornet

Little confused as my 340B in 22 Hornet is made in Chicopee Falls (1938-1960) though has "SP" date code in an oval. No Serial Number, patent #2585798 (as best I can tell, which I think was issues in 1952 timeframe?). Exact marking is PROOF TESTED, with 22 - Hornet under that and Patent 2,585,798 (?) under that. top of barrel near receiver marked SP in oval circle, with 60F (?) under it. Any thoughts as to when this rifle was made? Thanks!

"SP" in an oval is the Savage Proof stamp not a date code. The 60F is most likely the inspector stamp (60) and year code (F) which would be 1954.

Rifles with Date Code Stamp (1949-1969)

Thanks- I tried to post a pic but did it incorrectly- looks like 30F. tough to see but it can't be P as that would be 1963, and Chicopee is 1960 and prior.
Much appreciated.