One more time, when a universal receiver and test barrel are used for the reloading data, the chamber and bore are at minimum dimensions for that caliber. This means this data will generate the highest possible pressures. Meaning the chances of you getting higher pressures from your factory firearm are slim to none.
When a specific firearm is used this means a strain gauge must be glued to the barrel and a calibrated cartridge must be fired to calibrate the pressure readings. If this specific firearm has larger chamber and bore dimensions than a universal receiver and test barrel the pressures will be lower and the pressure reading will be ball park.
How many of the of the manuals use a universal receiver and test barrel that has a pressure transducer attached to the barrels chamber and gives direct pressure readings?
Below is from the manufacture of "PressureTrace" that uses strain gauges glued to the barrel and uses software guessimates for chamber pressures.
"PressureTrace will generate PSI estimates without calibrating the system to a factory load!
Using factory ammo or a load reference with known pressure to verify results is always recommended but we recognize each chamber will produce different pressures and wildcatters may have nothing for comparison. PressureTrace uses both thick and thin wall open vessel algorithms to provide reasonably accurate pressure estimates from barrel, chamber and brass dimensions. Unlike other products PressureTrace does not require a large correction "fudge" factor for pressure held by the brass but the system can still be calibrated to match other pressure systems. For safety, NEVER exceed the loads in a reputable load manual."
Below is a Quickload software guessimate of chamber pressure and velocity and it does not have the accuracy of a pressure transducer and chronograph.
Bottom line, the universal receiver and test barrel will always give the most accurate pressure readings and the strain gauges will give you close estimates of the pressure generated.
Start with the lowest start load and work up watching your primers and cases for pressure signs, end of story.
When a specific firearm is used this means a strain gauge must be glued to the barrel and a calibrated cartridge must be fired to calibrate the pressure readings. If this specific firearm has larger chamber and bore dimensions than a universal receiver and test barrel the pressures will be lower and the pressure reading will be ball park.
How many of the of the manuals use a universal receiver and test barrel that has a pressure transducer attached to the barrels chamber and gives direct pressure readings?
Below is from the manufacture of "PressureTrace" that uses strain gauges glued to the barrel and uses software guessimates for chamber pressures.
"PressureTrace will generate PSI estimates without calibrating the system to a factory load!
Using factory ammo or a load reference with known pressure to verify results is always recommended but we recognize each chamber will produce different pressures and wildcatters may have nothing for comparison. PressureTrace uses both thick and thin wall open vessel algorithms to provide reasonably accurate pressure estimates from barrel, chamber and brass dimensions. Unlike other products PressureTrace does not require a large correction "fudge" factor for pressure held by the brass but the system can still be calibrated to match other pressure systems. For safety, NEVER exceed the loads in a reputable load manual."
Below is a Quickload software guessimate of chamber pressure and velocity and it does not have the accuracy of a pressure transducer and chronograph.
Bottom line, the universal receiver and test barrel will always give the most accurate pressure readings and the strain gauges will give you close estimates of the pressure generated.
Start with the lowest start load and work up watching your primers and cases for pressure signs, end of story.
