Thread: How do you know when your brass is kaput?

thin spot, in general engineering, I say that because while I have considerable engineering and some combustion knowledge I have none specific to ammo and explosions (though an explosion is really just a very fast [mostly] un-controlled fire), so several possibilities,

The flame from the explosion will have a "front" as it goes off even and explosion takes time to happen, sort of like a weather front as the flame burns it maybe that that front impacts the wall just there so its erosion, and/or the flame front's temperature is causing a localised change in the metal like its being softened more than else where and/or its the highest pressure point hammering it thinner. You could send a cross section away to get the metal in that area put under a microscope to see if there is any sort of change.

c) Something in the way a full die is working that causes a thinning just there.

If you really wanted to know, a microscopic inspection might yield clues, in fact I suspect you would indeed see from that.

Also from what I can read some case manufacturers cases have a thicker wall, so they may cost a little more but last longer. I didnt know about this effect so that will probably send me in the direction of looking for a high quality case with the thickest walls as a starting/testing point.

thanks!