The Wby Mark V must be about the most tested and thrashed action available, given the very nature of the calibres. In addition you have the very large case head size of the 30/378.
And remember if you can shear off the 9 lugs you also have to shear off the integral bolt handle.
I find it very difficult to believe factor Wby ammo could do this. Wby factory ammo is full of powder and Norma would not get enough extra into the case for rifle blow ups, unless they loaded the wrong powder.
