Hi all. Long time reader, first time poster (I did make a valiant effort to find out this info on my own). I have enclosed a pic of each of the two 4" Pinned and Recessed .44 Mags I have come across. One is a No-Dash 629 (#N869206) and the other a 29-2 (#N645742). In my research I have heard words like "transitional" and "collectable", but I'm really only concerned with the years of manufacture (if they can specifically be pinned down). For some reason, I have made it one of my missions in life to find super cool "birth year" guns for friends and family. Thank you for your time.
Welcome! The model 29 probably shipped in early 1980, and the 629 in 1981. Others here have their own SN tracking data and may be able to get you a more specific date.
If they are both pinned and recessed they are not transitional revolvers (which would have had one feature or the other deleted), but collectible they sure are. Hope this is helpful.