I am aware of that. From what I have read on the subject it seems as though given the properties of the steel that the Mauser brother were working with they relied on mass and design to handle the pressures involved. But I have also read that many of these actions were rebarreled to 7.62x51 NATO post by the Spanish, so I assume that, subject to direct experience of those who have gone down this path before me, it can be done if one is armed with the rite information.
