[mrerick]

Here's a picture of some newly manufactured hold opens:




As you can see, there is a slight curve to the inner surface that runs on the pin in the frame. That appears to be missing from your hold open, and that may be allowing it to more out of proper position.

Here's a clear picture of the profile on one that looks almost new:



So, you may have one with wear, or that someone has improperly "adjusted".

Marc