I understand your points DC, and $400-700 for a trued and converted action and bolt is a chunk of a nice big custom action, but like you guys say, for a drag around field rifle, the tight tolerance customs may, or may not be the right choice, just depend on the crap you go through. If you already have a 700 and just want to open it up and rechamber, the price is obviously considerably less than a custom action.
I for one don't push my loads up to 75-80k psi, but maybe rarely during load development if pressure climbs unexpectedly rapidly at the top, and still I've never blown a primer at 80k psi. I would imagine I'm **** close, and may have just been lucky too. I do know the 700's lugs will handle that pressure in the event it's hit, but I will make a point for you you haven't made, and it might be fair to say if you did comprimise the case and gas was released, you might find small pieces of the Sako extractor could be let out the right raceway back toward you, no guarantee, but no guarantee it wouldn't... that's one thing the Savage offers proection against.
At any rate, pressure is pressure, reguardless of powder charge used, and casehead size on the cases are the same, thrust will be identical on the big 460 WBY with 500's if pressure is the same.
Remember, at a certain pressure, the brass will begin to under go plastic deformation and begin to squeeze into every opening available at the rear, usually at 70-75k psi it can be seen pretty vividly. 75-80k psi is a range that just ruins brass, but also you begin to run the risk of escaping gas in your face through the primer and weak spots at the rear of the case... A full case rupture on an M1-A I had, which destroyed the action, bolt, stock and op rod, clip, etc... let me know it's not a fun experience. Pressure was 81k psi when that happened using an unknown powder.
At less than 70k psi the big Weatherby cases will start to expand rapidly on the belt and finally they will not chamber, as this area cannot be sized back down. On the beltless Rigby case, this casehead expansion causes the brass to expand just in front of the web and can be sized back down, but only to a point a little better than the belted version... once the casehead expands to equal the chamber ID, your through using those cases, as the die will NOT size the web, or casehead down, only in front of it.
If you don't keep the pressure down to the point you're only getting .0005", ya 5 ten thou expansion or less on the belt on the second firing of virgin brass, with a load any hotter than that, the case will KEEP growing in dia across the web at that rate and you'll end up with case too tight to chamber in very short order. At anything much over 70k psi, you can't ever keep this from happening the pressure is just too great. Loosening primer pockets are simply a symptom of this excessive casehead expansion begining to happen. At 65-70k psi, the casehead will expand on virgin brass, but then will not expand any further, and primer pockets will not open up either. The softer the brass, and or the the thinner the web, the less pressure the casehead will handle and stay put and not expand further beyond the initial expansion.
The point is, the brass is the weakest link by far, not the action here. I practice with the brass I hunt with, so longevity does matter to me. Darryl runs his like a top fuel dragster, one trip and that's all that matters, top speed is primary, everything else comes at a higher price beacuse it's secondary.
For me, brass is like a partner which I spend a lot of time on, get to know and come to depend on, and I hate to throw it away, I don't care what I paid for it either.
