Savage 24 in their orig 22rf/410 chambering was not serial numbered in mfg made before 1968.
Neither chambering required a mfg'rs applied ser# under Fed law at the time ,,none for a 22rf long gun,,none for a shotgun.
After the GCA68 took effect, shotguns and 22rf long guns which had been exempt from the ser# requirement were then required to be ser#'d.
Savage started making the Model 24 in .222Rem before 1968 (20ga/222). Those and any other centerfire rifle cal version I believe would be ser#'d as the centerfire rifle caliber would have required it pre GCA.
(There are/were goof ups in the industry when the GCA came around and perhaps some production skipped out w/o a ser#. That happened at Marlin when they started making the Mod 57 in centerfire and didn't ser# the first 500 or so. The RF version wasn't orig numbered,,so why do these?)
The date code system that Savage used started in 1949. They continued to use it right into 1971 or even a bit further.
So you can find serial numbered shotguns and 22rf rifles with both date codes and ser#'s on them.
The date code portion of the stamping is the letter only,,any number (single or double) stamped along with it in the circle or oval is an individual inspectors ID. The ID can differ on the same guns date code stamping from the frame vs bbl.
Savage is not selfish when stamping inspector type number and letter codes on parts. They can be a mess of stampings and sorting out the internal factory control numbers/letters from the simple date code can be difficult.
The Sav Mod 24 started out as the Stevens 'Model 22-410' in the very late 1930's (Savage owned Stevens since 1920). An O/U shotgun version was the Stevens Four-Ten.
Savage renamed it the Savage Model 24 and re-intro'd it in '49 or '50.
The Stevens branded version (& 410 O/U ?) were discontinued at that point.
Plenty of different Models, caliber & gauges, Lots of variations on the insides over the life of production.
