I've been wanting to nail down a few specifics about S&W .44 Specials anyway, this seems like a useful place to try work this out...
These statements seem to be true from what I've gathered but please correct me if I'm wrong!
Not being Magnum or Rimfire, they'd have never been recessed.
The 624 was never introduced until pinned barrels had stopped. Prelock, yes, dashes?
The L-frame was also never pinned, so the 696 was not. Prelock, yes, no dash and dash-1.
In blued or nickel the .44 Special has a much broader history, of which I am sadly mostly ignorant. Names like triple-lock and HD come to mind. This may not be the right forum for the majority of that story, but surely there are a few dashes of the 21 (fixed) and 24 (adjustable) that came after '45 and before locks.
I'll be watching this topic to hopefully learn.
My favorite handgun to shoot, bar none, is a Rossi 720, 3" K-frame sized 5-shot with RR/WO adjustable sights and a nice rubber factory fingergroove grip, fluted cylinder and standard hammer. If S&W had made one, I'd have it, but sadly the L-frame is significantly larger, and they cost so much I'll probably never be able to afford one.
I had and sold a Taurus 445, a 2" fixed sight steel 5-shot. Not nearly so much fun to shoot.