I hope I'm in the correct forum .... if not, I apologize . I have a model 24V in .222/20 and it has a four digit serial number on the left side of the receiver with no letter prefix. It simply reads 48XX. I didn't think that Savage put serial #'s on them until 1968 ....is that not correct ? I searched the available data and can't find any info on serial #'s with no letter prefix. I also have a model 99 in .308 Win. and used the available data to date it to 1977 ..... thanks for providing such a useful site.