We've discussed this ad nauseum before, but here's a few things you're not considering. First, the brass can also fail, leaking gas out of the action. Leaking gas is a danger itself, as it can damage the shooter. It also carries particles of brass or steel or powder with it, which can harm the shooter. it also can cut the steel, starting a chain of events that can cause other failures. Second, the springiness of the action you asked about can cause brass failure. The springiness of the action is caused by the fact that all steel elestically stretches, then stretches non-elastically (yields), then catastrophically fails. The arrangement of the block, hammer, hammer pins, etc on a rolling block adds several components to the action that have inherent movement to them, and that can stretch or yield even before failing, with the result that the action stretches open slightly. The third thing that you arent taking into account is incremental failure, or localized failure. An analogy to this is tearing a phone book, a stunt that is sometimes done to amaze onlookers with the persons strength. If you try to tear the phone book all at once, it is un-doable. However, if you offset the edges slightly, so that you start tearing at the front or back, you can easily rip the book in two, since once it starts to tear, it continues with less effort than if you were to start the tear at full width. If an action or barrel gets gas cut by escaping gases at high temp/pressure, it can start to "tear" at the cut, and the failure can perpetuate at less than full hoop strength. A barrel that splits shows this, once the split starts at a thin point, it goes up the barrel through thicker areas. You are only considering catastrophic failures (blowups) too. I would consider the action jamming a failure, or bent brass, stretching, bulged primers or bent extractor. Many of these things could happen with high pressure rounds without blowing up the action. dave
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