Well, I asked about in the gunsmithing forum, and it was suggested that the cylinder stop, which also acts as a sear, might be the culprit.
Sure enough, there was JUST ENOUGH wear that it would not seat in the hammer notches properly, thus causing it to fall.
A trip to the Dixie Gun Works web page (
www.dixiegunworks.com) yeilded the proper parts, which will be put on order on payday.
Looks like new life for the old warhorse.
Not only the cylinder stop, but the following will be replaced:
cyl. stop
hand and spring
hammer
mainspring
trigger/stop spring
A complete overhaul for about $31, plus shipping.
I'll post an update when it gets taken care of.