Could anyone help me with dating vintage Winchester shotshell boxes? By vintage I mean late 1800s to 1962. I’ve searched but can’t find helpful information. 

I would like to know how to decipher the codes on the flaps.

I have some two piece boxes that do not have codes. Some of which are still sealed. I’m thinking these are 1900 to 1940s mfg.

Any help is greatly appreciated.