Hello again, WF...
Here are three (3) detailed photos as you asked for. Sorry about the lack of clear focus...I think I am pressing the capabilities of my digital camera.
There is a bar (in the white) enlaid into the striking surface of my hammer. This bar tapers and extends down to the upper surface of the sear bar; which I think blocks any double-action trigger pull. The tapered end of the bar is flexible and rotates along the sear bar when the hammer is manually cocked to allow the trigger to go to its single-action position and then the gun can be fired.
Let me know what you think...
Best Regards,
Pete... <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />