Harrington & Richardson Model 922 (Pre-1940)
4th Variation (Birds Head)
Internal Function (Continued)
--.22 Caliber, 9 Shot Revolver--
Here the internal firing mechanism is in its normal hammer down,
With this revolver several peculiarities make a further functionality explanation necessary. As shown in the above images, the "Lifter" pushes the hammer when the trigger is squeezed. Then releases hammer just before it would otherwise be caught by the sear.
The cylinder stop or lock is machined into the top side of the trigger. This design results in the cylinder stop not even sticking through the frame and the cylinder NOT being locked into place in the normal hammer down position. The friction pin is supposed to provide resistance to the cylinder turning too freely. The result is that the cylinder can be easily turned at all other times! Worse, the cylinder is machined to stop the cylinder Lock only from over travel! More explanation later.
The sear is separate from either hammer or trigger and is actually exposed behind the trigger. Squeezing the trigger when the revolver is in the cocked position results in the back of the trigger pushing the sear to disengage from the hammer. Positioning of the sear during assembly seems to be a difficult trick. I use a very short slave pin which keeps the sear and its spring in place on the trigger guard, but still allows the guard to be installed into the frame. The guns sear pin can then be pushed through, replacing this small slave pin. All while holding the sear in place.
A "Friction Pin" and its spring falls out of this hole when the front of the trigger guard is removed. Careful not to lose these pieces, which must be replaced correctly during assembly. The friction pin applies upward pressure against the bottom front of the cylinder.