I don't recall the details of the actual load, perhaps someone here does. Some 10-12 yrs ago maybe longer, Buck Hamlin took a 12ga hammer L C Smith having welded bbls, don't recall now if they were twist or Damascus. Barrels were heavily pitted & considered very poor condition. He lengthened the chambers to 3˝" & proceded to begin firing the heaviest loads of Blue Dot listed for 3˝ shells in Hercules/Alliants manuals. As nothing unusual occured he began increasing the load & continued doing so until he just physically ran out of space in the hull, but never succeded in Blowing it up.
Note also the guns mentioned above which were blown up, Bells's test being at some 30K psi, none blew at the chamber/cone juncture, nor down the bbl.
It should not of course be supposed that in a well designed & made gun, using any normal loads that the wall between the chamber & extractor hole is a particular weak spot. Those which did blow at this point were not ordinary.
