I know this is primarily a computer forum, but I know there's people around here like DocM that may be able to help me so I thought I'd give it a shot.
So I bought a Heritage Rough Ryder .22 caliber revolver from a friend of mine, and I then gave it to my brother. The friend needed money to make it through a school, so I did him a favor and got a sidearm for my brother so he'd have a snake gun when we go out in the woods. So anyway, after test firing it a few times we noticed that if you point it at an upward angle, the cylinder fails to rotate. It has been dis-assembled before by somebody who didn't know what they were doing because there are some obvious scratches around some of the screw heads. I took it apart and found the culprit, but I'm not sure of what the technical name for this part is called.
My Taurus has something similar but it works by a different mechanism. Basically the larger part here is what I call the "lifting arm", and when you pull the hammer back, this arm lifts up, the teeth catch on the gear on the cylinder and rotate the cylinder. The spring depicted in the attached picture is supposed to be much longer, and presses against a recess inside the frame and holds the lifting arm forward so it always makes contact with the cylinder. With this spring being broken off (I know it's broken because it doesn't make contact with anything since it's far too short, and the end of it looks jagged and uneven when you get up close), what happens is that if you're firing downward or straight forward, it works fine, but if you point it even the slightest bit upward, when you pull the hammer back, gravity causes the lifting arm to fall back into the frame instead of catching on the cylinder.
I've found a parts list on the Heritage Mfg. website, but I don't know what the technical name for this spring is. If one of you could help me I would really appreciate it. Here is the parts list on the Heritage website.