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Thread: Wilcats and Pressure

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  1. #1
    dog chaser distant stalker's Avatar
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    Quote Originally Posted by Spanners View Post
    Sorry - should have been clearer.. 87654psi was a number I pulled out of my arse, but 88k is a number I have seen mentioned a few times as to the strength of the brass - was just wondering where that number came from thats all, though from your reference to 88k and not 87654 that you were using it as a figure.

    I did a fair bit of dicking around with cases and the gun etc,
    As far as pressure goes, I completely avoided the topic via strain gauge as I give it little merit regardless of brand in regards to a number. I ran racecars on dynos for years, and know the differences between machines - and its the same situation.
    We're not dealing with something thats been shot for 50 yrs in the same construction of brass and receiver and thus pressure really has no influence IMO
    If this case was designed before any 'magnums' were CIP or SAAMI approved, would you load to 50k psi and call it quits? of course not - thats where and how magnums were developed. Are we not talking about a magnum magnum now? if so then why are we limiting things through a set number from 30 years ago rather than working with the case to see where it goes?

    If you can load the same case 5 times without FL sizing, primer pockets are tight as a tiger and there are none of the ABC signs from common sense reloading, then pressure of XXXpsi means what?
    Back to a point I made earlier - overloading is loading more than a standard - the standard appears to have been set by pulling a number from thin air or from a completely different caliber 1/4 of a century old
    This should have been your first post and things would have stayed on track better. The signs your mentioning would suggest pressure is ok
    You yourself mentioned how hard it is to know pressures. Is it then possible to know accurately the strength of the action then know the pressure of the load then factor in the safety buffer or is it all based on experience based estimates? If it is left to estimates then until that action is fired x amount of times at x pressure and examined you won't be able to know. I would like a good safety margin

  2. #2
    Official Cheese Shaman Spanners's Avatar
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    Quote Originally Posted by horihunter View Post
    This should have been your first post and things would have stayed on track better. The signs your mentioning would suggest pressure is ok
    You yourself mentioned how hard it is to know pressures. Is it then possible to know accurately the strength of the action then know the pressure of the load then factor in the safety buffer or is it all based on experience based estimates? If it is left to estimates then until that action is fired x amount of times at x pressure and examined you won't be able to know. I would like a good safety margin
    Maybe I know what I'm thinkging but its not getting out, but I feel like I have repeated the same info in that post a number of times.

    I;m the sort of person that will call BS on anything unless it makes mechanic sense as far as numbers and calcs go, or I have witnessed it and seen it for myself to the quandary, however Ill also admit any time I'm proven wrong and will also sit back and go 'holy shit - you're right and it works'
    If you can better yourself and learn something you are onto a winner, if you can change your prospective totally based on real world in your hands info, then I think you win even more.
    I had a 'Holy shit - you're right' moment the other week end - and I considered myself towards the end of what I could learn as far as loading goes to be honest - its great to be humbled, and to also be a part of 'you're the only person who knows this' and to see and touch WHY it works

    I'll admit I was sceptical on KGs loading of the 375 based on the rhetoric I have read here. However after doing the investigation work on the cases etc, and now that the fact that 67000psi is a number to be used as the benchmark for his 'overloaded' cases as set by someone elses belief, that KG is ahead on paper and in his real world development.
    I'm not goign to buy a gun from either party in the fight, however you come up with a caliber/loading etc that works and ticks all the correct ABC boxes, and you;re ahead of the pack, you get a pat on the back - regardless of who you are.
    If you want to bash the opposition because you're coming 2nd in the race, then you can only expect a few swing back - no?

    The whole point of this is a new case with no info/data - it has turned into the 375 big dicks competition, which isnt bad as it is an example of exactly the topic at hand.
    You can do the math on action/lug strength, the number you get whether raw or with a FOS will surpass the brass strength - simple mechanics again.
    The fact that the traditional (I steal from Bladbob) ABC signs of pressure are not being exhibited in the brass then you havnt hit the brass's failure point, and more than likely far from it.
    I will note that where you WILL run into excessive stress of an action is when is with catastrophic brass failure in the forum of a case head separation.
    In this situation, you are applying all the force to the action.
    There is a good book on the 1903 which goes into alot of the action and cartridge development - tests they did with turning barrels down to almost waffer thing between the chamber and OD, deforming cases to MAKE them fail and induce casehead seperations and thus load the lugs, different heat treatments etc - all VERY interesting stuff. They TRIED to blow guns up on a regular basis - all this stemmed from 100+ yr old heat treatment processes where it was no more scientific than looking at the colour of the steel with crap lighting. We are FAR more advanced in this age.

    Maybe the guy who has fired 500+ rds in the chambering and has played with a couple of different reamers etc has learnt someone over the guy that orders a reamer off the net and fired 10rds to draw his conclusion?

 

 

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