Hoping to get a estimate on a date for this revolver. Just found it in my grandfathers shop while cleaning. No box or papers but this thing has never been touched. Looks like he got it, put it up for an emergency and forgot about it. Its just been sitting and waiting for someone to find it. Will add pics when I get on laptop again.

2.5 inch 38 special
Stamped mod-36
Serial number 1921xx
Diamond on wood grips around grip screw

Everything I have seen leads me to believe this is pre 66 but post 59. Not totally sure. Serial number charts only give me a ballpark guess and the stamping on crane have me confused. Not sure if its a date ( doesnt match date chart if it is ) or a factory code. My research leads me to believe 1960-1964 range. Would like a closer estimate if possible. Stamped 6 10 86 a large Q and a small w on crane. Has ramped front sight, firing pin on hammer. 2 screw model. Not sure what other info would be relevant.

Thanks in advance. Have a great weekend.