A few observations and comments on Gitano's post from someone who doesn't purport to be an "expert" in anything. Ackley, DeHaas and some others did tests on actions which were very helpful and informative to us' especially those of us who don't have the facilities or knowledge to run our own tests(not to mention the cost). I don't think ALL those who urged caution did so out of ignorance, but from the standpoint of prefering to err on the side of safety, kmowing that some people will push things too far. Now if we look at the pre-98 mausers and some others, the locking area of the bolt and receiver are the same size as a 98. The Husqvarna actions were made with a M98 type of bolt at the back end, but the front end was about like the M94/96 Swedish military actions and the receiver was the "small ring" size. Some of them were chambered for belted magnum cartridges. I think the question is not so much about the yeild point of the receiver/bolt as it is the case, in the event of a case weakened by stretching during resizing or a chamber with excess headspace. The M98 will handle escaping gas better, at least in theory. Another aspect is the heat treating of the receiver/bolt. If they are too soft they might stand an overload well, but gradually develop excess headspace due to the lugs seating into the receiver while using loads well within the safety margin. I have worked on a pair of 1909 Argentine actions which were about Rc 15. This is about the same as a piece of 1018 cold roll. One I lapped the bolt lugs in and had re-heat treated. The other was so soft that the bolt sleeve lock had worn a notch into the rear face of the rear receiver ring where it made contact, the rear of the extractor had worn a groove in the bolt and the ejector had worn a groove along the bolt where it rubbed as the bolt was opened and closed. Both were original military barreled actions. Both had set the bolt back into the locking shoulders to the point that metal had extruded out against the bolt body. I doubt that either had ever been fired with anything but military issue ammo.
Some of the Spanish receivers were very soft, as well, and the quality of the machining left something to be desired. My feeling is do your research, proceed with caution, but remember you won't shoot as many rounds in a lifetime of hunting as target shooters and prarie dog hunters will in a season. If it does what you expect of it then don't worry about what others think of it. By the way, I like that Martini-Enfield. Always wanted to build one myself, but never got around to it. L. O. G.