So I found out why the wheel on my Webley can still rotate left and right about 1/8in when locked and ready to shoot.
This is my first and last revolver so I have no experience as to whether this is something to be expected.
There is a rectangular notch above the trigger that clicks into a larger/wider rectangular depression on the wheel. The depression Im talking about is along the center under and above the letter B on the diagram.
Some immediate concerns are...if there is so much of this movement...the pin might strike the primer offcenter and the chamber may not even perfectly align with the barrel...thus deforming the bullet and creating other problems.