I picked this 3979 up for peanuts a while back and since one entire scale was gone I decided to rehandle it with OD micarta as an EDC. The knife has great snap and is my favorite EDC (for now at least). I got inspired to try OD micarta from a thread a while back that had pictures of a beautiful Camillus 23 done in OD micarta. I still haven figured out how to get it as smooth and pretty as that one! I read that Winchester started producing knives after WW1 and stopped because of other demands when WW2 came along. So I assume the 4/7/08 patent stamp on the punch stands for 1908. Before and after pics:
"Better to do something imperfectly, than to do nothing flawlessly." ~ Robert H. Schuller
Your knife was most likely made between 1922-1932. The pat date is a Naponoch patent date for that particular punch blade and Winchester used them up after they purchased Naponoch. Someone with more knowledge can correct me if I'm wrong.
If you ever decide you just dont like it anymore let me know!!