JHP load data

Of course 50,000 CUP is 50,000 psi. They calibrated the crushers with dead weight or hydraulic pressure.
Too bad that deforming the crusher takes time and movement. Not much on a yardstick, but a lot compared to flexing a quartz crystal. It does make a difference.

Where we part ways is saying that a gun designed for 50000 CUP back when it was called psi because of mechanical calibration is being overloaded now that we know the same ammunition shows 60000 psi on an electronic transducer. The loads are not producing higher pressures, they are producing higher readings when tested by a different method.
As I said, SAAMI doesn't think so, they don't care which page you read; the .30-06 is listed at both 50000 CUP and 60000 psi.


As to .38 special, ol' Phil just didn't care. He shows Special loads the same as .357 loads. 16 grains of 2400 and his 146 gr bullet got him 35000 CUP in either case. But he adjusted the seating depth kind of like Skeeter did years later with the double crimp groove Thompson bullet.
A lot of Sharpe's loads are specified by seating depth, which directly affects powder space and pressure rise. Nobody knows anything but OAL any more.
 
Where we part ways is saying that a gun designed for 50000 CUP back when it was called psi because of mechanical calibration is being overloaded now that we know the same ammunition shows 60000 psi on an electronic transducer. The loads are not producing higher pressures, they are producing higher readings when tested by a different method.

As I said, SAAMI doesn't think so, they don't care which page you read; the .30-06 is listed at both 50000 CUP and 60000 psi.
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I just checked one of my older books, and the designers of the era sized the locking mechanism of the M14/M60 based on the assumption that the maximum load the bolt was going to hold was 50,000 psia. Material thickness, safety allowances, shear load, etc was all based on 50,000 psia. Designers took 50,000 cup to be 50,000 psia. If the loads of the period were in fact putting out 60,000 psia, then the structures then were being exposed to a load over the design criteria. And that would be true then as it is now.

Sort of like Hillary Clinton's emails. Just because she was too stupid to know she was sending Classified material over a non secure network, does not mean she did not commit a security violation. She committed a security violation then, and she is still guilty of a security violation now.
 
Wonder what Mr Garand calculated the original of that design for.
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He would have used the maximum pressures of the cartridge the mechanism used. I don't have any pre WW2 era Military Specifications, but I do have a copy of MIl C 1313 F, Cartridge, Caliber .30, Ball, M2

Chamber Pressure The average chamber pressure of the sample cartridges shall not exceed 50,000 (psia)

This Rev F spec is dated 1971, Rev E is dated 1968. The pressures in the specification are not, to repeat, not given in CUP units as CUP was assumed to be Psia. I am certain that Mr Garand would have used the same 50,000 psia to design the locking mechanism of his rifle as other data sources indicate that 50,000 psia was the pressure limit of the 30-06 going back to WW1.
 
I have a couple hundred 158 gr JHP bullets to load in 38 & 357 magnum. Does anyone have a decent load for these ? They will be fired in a S&W model 19 with a 4" barrel.
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Use ANY load data source and you will find more loads for this combo than any other on the planet. Start with the free ones on Hodgden.com and Alliantpowder.com with powders you already have. .....and for the love of Pete, ignore this thread!!!!!!!!!!!!!!!
 
Any load data I get from a forum member I first verify in my manual that it is within the starting load and maximum load data in the manual. I would never just take load data off a forum and load it. I am just not that careless or reckless. I cherish my hands a lot.
A pet Load from another forum member can save quite a bit of money and time by giving a good starting point but it has to be checked out in a manual as being a safe load before I load it.
 
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