I'm thinking that this dimension is the one that controls when the bolt comes up (the timing). Because as the trigger is pulled back, this leg rides up the top of the cam and drops off, that is when it rotates to engage the cylinder.
http://i613.photobucket.com/albums/t...brid/dim-1.jpg
And so this dimension really is insignificant:
http://i613.photobucket.com/albums/t...brid/dim-2.jpg
And this one only makes it easier and smoother for the bolt to reset and wait for the next time the hammer comes back.
http://i613.photobucket.com/albums/t...brid/dim-3.jpg