Self-Winding movement with Patent No. 166843 (31-01-1934). Movement Calibre: 28-20
In reply to I love this watch, I do not by Geoff Baker
'Champ' is the Bulova name for this model, and it is based in no small part on the company that supplied the ebauche: Farbrique d'Horlogerie la Champagne. Champagne also made watches complete, and had names like 'Aster' also on the dial.
The automatic winding system is the 'Pendule' type, and it acts exactly as you might think- it swings back and forth, with small blade springs as dampeners, like a bumper. It would have been amongst the earliest Bulova automatics, there were also 'wig-wag' style movts. As I've said elsewhere, these are rare indeed.
In reply to I am trying to figure out how by esk51
The case serial number you listed is 5258933which would most likely be 1935 and not 1929.
This was an extremely limited run movement and I think it was most likely just that one year as this was the height of the Depression and anything that was more costly to produce didn't sell many units.
In reply to I am trying to figure out how by esk51
Here's the updated entry for the Bulova 13AP in the movement database.
Some very good information is being found on the watch. I appreciate everyone's input. What I was referring to on the case was the upside side down bell like stamp with the line on top which according to the Bulova codes would date the case or movement to 1929? That was in conflict with the patent date? I was trying to square that circle so to speak. Thank you everyone !
In reply to Some very good information is by esk51