The picture posted by Revdocdrew, is also shown on page 89 of "Shotgun Technicana" and is, as David said, of an L. C. Smith that was blown up by a faulty reload containing a "double" load of shot? In any case, it has nothing to do with the topic of long shells in short chambers.
To further remind those who may need reminding, Sherman's conclusion was that firing a 2-3/4" shell in a 2-1/2" chamber, WHEN THE SHELL WAS OF A PRESSURE LEVEL THAT WOULD BE ACCEPTABLE IN THE GUN AT HAND, would not likely be danger. Firing shells producing much higher pressures than what would be appropriate for the gun at hand is of course, dangerous, but not because of the shorter chamber length. We all are reminded to keep pressures lower for our older guns, regardless of chamber match or mismatch. That is the really important thing, here. Be safe.
Lots of room between being reasonable/safe and being paranoid.
