From 24hrCF,
Just curious, but if you load at 65k psi, how high is the pressure of the outliers? I have always thought that you should load to an average pressure such that all loads within 2 standard deviations don't exceed the max allowable pressure.
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John Barness answers....
Exactly. That's why the SAAMI standards for average pressure in any cartridge are under 65,000 psi.
Some cartridges tend to show more variation in the pressure of individual shots than others, the main reason the average pressure standards vary for different modern bolt-action rounds (though some are lower because the round is an old one).
The short-fat magnums tend to show less pressure variation than other rounds, the reason their average pressure standards are higher than for most others. But they are still usually under 65,000.
_________________________
JB
"New opinions are always suspect, and usually opposed, without any other reason but because they are not already common." -John Locke
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Chuck,
This is one reason I read J. Barness and not much T.Wieland.. John writes interesting and informative articles.
T. Wieland on the other hand seems to like to appeal to the emotional ignorance of his readership...
Either he is a lazy writer, or thinks very little of his reader ship intelligence, or he is just a little azzwipe..
Pitiful and pathetic won't you say Chuckie??
Just curious, but if you load at 65k psi, how high is the pressure of the outliers? I have always thought that you should load to an average pressure such that all loads within 2 standard deviations don't exceed the max allowable pressure.
------------------------------------------------------------------------------------
John Barness answers....
Exactly. That's why the SAAMI standards for average pressure in any cartridge are under 65,000 psi.
Some cartridges tend to show more variation in the pressure of individual shots than others, the main reason the average pressure standards vary for different modern bolt-action rounds (though some are lower because the round is an old one).
The short-fat magnums tend to show less pressure variation than other rounds, the reason their average pressure standards are higher than for most others. But they are still usually under 65,000.
_________________________
JB
"New opinions are always suspect, and usually opposed, without any other reason but because they are not already common." -John Locke
---------------------------------------------------------------------------------------
Chuck,
This is one reason I read J. Barness and not much T.Wieland.. John writes interesting and informative articles.
T. Wieland on the other hand seems to like to appeal to the emotional ignorance of his readership...
Either he is a lazy writer, or thinks very little of his reader ship intelligence, or he is just a little azzwipe..
Pitiful and pathetic won't you say Chuckie??




























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