It's worth noting that in all three of the blown chamber incidents I have personal knowledge of, the gun provided feedback before the catastrophic event.
They were all the result of defective shells. No mystery as to the cause in any of the accidents.
1. 11-87 turkey gun (brand new) fed shells loaded by accident with 36 grains of Green Dot and 1 1/2 oz. of lead shot. It withstood the first shot. The turkey was still flopping around... so.... "the bolt was very sticky, but I was able to chamber the second round by cycling the bolt manually". Boom.
2. Lanber O/U fed the first products of a very young man's reloading efforts. Trap shooting with the bottom barrel. Several very loud reports, difficulty opening the action, yet he persisted and nobody stopped him. Boom.
3. The aforementioned Italian made, very well regarded, and almost new O/U. Recently proofed by Italy at over 18,000 psi. Sporting clays. New shells, imported from a CIP compliant country. After shooting the lower barrel, the gun was very difficult to open. This was attributed to the 'newness' of the gun. Next, shot... Boom.
Note the pattern. The gun gave a warning in each event that something was wrong. We can learn from that.
