Originally Posted by keith


The designer never gave metal fatigue a second thought.

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Almost certainly neither did Mauser before he designed his bolt actions. .

Have you seen examples of fatigue failure on these actions? Documented cases? Where have the cracks appeared? How many load cycles? Do you have any good pics of the fracture surfaces? Have you done any crack testing (MPI, dye penetrant) on these actions?

Originally Posted by keith


More of the issue is working hardening of the lug, it shearing off, with the bolt coming back into your face.


Again, any actual examples? Work hardening required repeated plastic deformation - a fair bit of it too, to be significant, so how much plastic deformation had there been of the lug before failure? What of the root of the bolt handle? Got any pics?