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| one of us |
Does anybody know what 62000 CUP = in PSI? My 458 Lott has this much CUP shooting a 500gr bullet over 2300 FPS | ||
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One of Us |
There is no direct translation and any translation you may find is really just a best guess. Rusty's Action Works Montross VA. Action work for Cowboy Shooters & Manufacturer of Stylized Rigby rifle sights. http://i61.photobucket.com/alb.../th_isofrontleft.jpg | |||
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One of Us |
It's extremely doubtful your Lott is at 62,000 CUP as this (very loosely) translates to 76,000 PSI BTW...Rusty's comments are correct! /////////////////////////////////////////////////////////////////////////// "Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery." Winston Churchill | |||
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One of Us |
I think 400 NitroExpress said it best. . .
Rusty We Band of Brothers! DRSS, NRA & SCI Life Member "I am rejoiced at my fate. Do not be uneasy about me, for I am with my friends." ----- David Crockett in his last letter (to his children), January 9th, 1836 "I will never forsake Texas and her cause. I am her son." ----- Jose Antonio Navarro, from Mexican Prison in 1841 "for I have sworn upon the altar of god eternal hostility against every form of tyranny over the mind of man." Thomas Jefferson Declaration of Arbroath April 6, 1320-“. . .It is not for glory, nor riches, nor honours that we are fighting, but for freedom - for that alone, which no honest man gives up but with life itself.” | |||
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| one of us |
If your load is 62,000 CUP you had better back it off at least 9000 CUP! The SAAMI MAX AVG Pressure for the 458 Lott is 53,000 CUP as I recall. Vapadog, I could believe a Lott loaded to 76000 psi +/-. | |||
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Moderator |
55,000 roughly equals 62,500 psi... MORE OR LESS jeffe opinions vary band of bubbas and STC hunting Club Information on Ammoguide about the416AR, 458AR, 470AR, 500AR What is an AR round? Case Drawings 416-458-470AR and 500AR. 476AR, http://www.weaponsmith.com | |||
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| one of us |
I figured it up on a form I used all the correct figures. It is on the web. I certainly hope it is wrong. My 338 RUM has 65000 PSI but 76000 is alot more. | |||
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I'd rather believe you meant 62,000 PSI and not CUP /////////////////////////////////////////////////////////////////////////// "Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery." Winston Churchill | |||
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Aaahhhh....yea I know.....you must be talking about the .458 Lott AI  /////////////////////////////////////////////////////////////////////////// "Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery." Winston Churchill | |||
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One of Us |
A good read which tries to explain. Also see Lyman Reloading. http://www.shootingsoftware.com/ftp/psicuparticle2.pdf Jeff,Hogkiller what do ya'll think of the graphs? Semper Fi WE BAND OF BUBBAS STC Hunting Club | |||
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Vapodog, The 458 Lott AI is precisely what I had in mind.  | |||
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| One of Us |
[QUOTE]Originally posted by invader66: A good read which tries to explain. Also see Lyman Reloading. http://www.shootingsoftware.com/ftp/psicuparticle2.pdf [QUOTE] I shall consider myself re-educated on this matter. Thank you for providing and excellant link. Rusty's Action Works Montross VA. Action work for Cowboy Shooters & Manufacturer of Stylized Rigby rifle sights. http://i61.photobucket.com/alb.../th_isofrontleft.jpg | |||
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| one of us |
Some of the problems with the analysis is that his 93% is effectively an average - look at the graph of SAAMI maximumx and see that some of the cartridges are on his line - and some are really far off, much more than just 7%. Even if you believe in this method and are trying to use some old loading data that gives a max of 50000 CUP for a rifle that you want a 60000 PSI load. You do the conversion of 50000 CUP and get 57891PSI, the error factor is +/- 7%. So your PSI number is actually a range from 53839 to 61943. So do you add more powder, thinking you are only at 53K psi, or do you use a little less to get down to a desired 60K psi? This is why ballisticians say NOT to try and convert CUP to PSI. Mathematics allows this, but real world engineering doesn't. | |||
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