Lockin' on the Link
Here ya go Jammer. Put on a pot of coffee and settle back.
http://www.thehighroad.org/showthread.php?s=&threadid=56380
On the second picture...the one of the barrel feet, viewed from the front of the barrel...it looks like the pin is beatin' on the tips of the feet, and they look kinda deformed. Hard to say from the pictures, so I don't know if Dave has actually cut a light, secondary radius in the feet to help support the lockup...but the crosspin is stopping near the tips, where they're not as sturdy as they are down in the radius...or what I lovingly call "The Cradle."
Stopping the slide on the tips of the feet leads to damage much earlier if the slide is allowed to go to battery on an empty chamber...Not as critical as long as the gun is feeding ammo.
Locking on the link is pretty common in factory ordnance spec guns...though Springfield has gotten much better lately with correctly fitted links on correctly spec-ed lugs...and as long as the lockup isn't tight, won't do any real harm for a while, other than peen the tips of the feet backward and delay linkdown timing to some degree. From here, it looks like
the link is locking the barrel vertically about a 16th of an inch.
Long-linking is a way to get more lug engagement in the slide, but generally works against accuracy because the barrel is supported on one center point instead of being solidly supported on two sides...as in when it's locked on the lower lug. The link is NOT supposed to provide vertical lock to any great degree...The function of the link is to unlock the barrel. It also acts as a sort of guide to keep it tracking in a fairly straight line, but that's incidental.
It also has to unlock the barrel at the right time...and the center-to-center length controls that.
Locking hard on the link also stresses the link pin hole in the barrel lug, and
can often lead to it wallowing out into an egg-shape...creating slop and further delaying linkdown timing. Many factory guns do lock on the link to some degree, and allows the gun to function well for a long time. Forcing the
barrel into tight vertical lock with the link will cause problems sooner rather than later. Delayed linkdown timing can damage the locking lugs on the barrel and in the slide if the barrel doesn't get down out of the way in time.
A too-short link can prevent the barrel from unlocking at all, if it's short enough...but for different reasons. The short link starts to unlock the barrel
while the slidestop pin is still under the lug. The lug and pin get one another into a bind, and the link is too short to let the lug off the pin. Damaged or sheared locking lugs result...or even a cracked slide.
Hope this helps...