The Accurate Reloading Forums THE ACCURATE RELOADING.COM FORUMS Rifles Big Bores CUP to PSIGo | New | Find | Notify | Tools | Reply | |
| 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 | ||
|
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 | |||
|
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 | |||
|
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.” | |||
|
| 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 +/-. | |||
|
Moderator |
55,000 roughly equals 62,500 psi... MORE OR LESS jeffe opinions vary band of bubbas and STC hunting Club Words aren't Murder - Political assassination is MURDER 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 | |||
|
| 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. | |||
|
| One of Us |
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 | |||
|
| One of Us |
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 | |||
|
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 | |||
|
| one of us |
Vapodog, The 458 Lott AI is precisely what I had in mind.  | |||
|
| 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 | |||
|
| 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. | |||
|
| Powered by Social Strata |
 | Please Wait. Your request is being processed... |
|
Visit our on-line store for AR Memorabilia