Another entry level question! Is pawl of a Walker revolver supposed to clear arbor when hammer is cocked without cylinder in place? My Uberti doesn't do that and the pawl always sticks before half-cock. With cylinder in place this phenomenon, fortunately, doesn't occur as ratchets push the pawl back somewhat. It's also fairly easy to push the pawl with your fingertip if it's necessary to cycle the action field stripped.
When looking at relief cut on the arbor rear it seems to me the arbor might be slightly canted, when compared to pawl window in the frame. Is the arbor threaded? Assembly line worker at Uberti has tried to get some extra relief by filing the side of the pawl. Fitting seems very rough and there are all kinds of dents and scratches in the pawl tip. When it comes to timing, bolt (cylinder stop) goes into cylinder notches at the very same time when hammer reaches full cock. According to discussion here, this is correct for open top. Bolt drop is fairly late, however, and I guess the bolt is partially over the notches when drop occurs.
http://castboolits.gunloads.com/show...=1#post3457523