....The root cause of the failure is as simple as that....
....A microscopic analysis of the failure and adjacent areas may conclude otherwise.
Until somebody does that, we're just guessing.
There's a failure tag in the picture with a clear reason, no guessing. It is the law there and recognized not only by that nation, but all other CIP member nations. Even though we're willing to question that recent arbitrary proof changes are wrecking guns that likely would've passed under previous standards, I still think it's a slap in the face of a classic gun expert who couldn't anticipate an elastic limit failure point, but knew if it were on face or not.
edit to add, thanks much Toby for your follow up comments. I don't question your decisions for a moment, only wondering out loud if this process assures us of anything.
