Hey guys... the discussion of SAAMI, CIP, reloads, etc is really not relevent to what we observe with these blowups. If Bell's tests showed anything, they show how tough even old guns are. The recent blow ups I've heard of involved some really fine modern guns, all proofed by either government agencies or the maker to at least 150% of normal pressure. It's likely that the guns will stand double, or greater, normal pressure before any signs of damage. They don't and shouldn't "blow up" with any reasonable load and most that are well past reasonable. I doubt that ANY quantity of correctly functioning modern smokeless shotgun powder that could fit in a shotshell would cause what we observe here. They usually survive even the dread 20/12 accident without the chamber failures we are seeing.
What we see is a detonation. The powder is not buring smoothly and progressively, it's releasing it's energy all at once. Like a grenade. The pressure spike is obviously enormous. This is an explosion to be sure... something is taking the shotshell out of it's normal operating range and turning it onto a bomb.
The story of the 101 on the Shotgunworld thread has my attention. Note the 'delay' before the gun detonated.
Have any experiments been conducted to simulate 'double ignition' of shotshells? The scenario I'm thinking of would be a faulty primer that burns in two phases. Phase one simply heats the powder charge up, phase two very shortly after ignites what is then a preheated charge. Is it this or something similar that causes detonation?
Perhaps someone with industry experience will comment.
