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Old 06-15-2015, 03:37 PM
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glowe glowe is offline
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Originally Posted by aurora40 View Post
I doubt they are linear. If the pressure doubled, I doubt the velocity would double. Because the more the pressure gets the bullet moving, the sooner it is out of the barrel and the less time that pressure is acting on it. Double pressure for the same amount of time might double the speed (though friction isn't linear either), but when the distance and not the time is fixed, they won't have a linear correlation.
One must remember that pressure measurement is the maximum pressure in the barrel. Looking at a pressure gradiant throughout the length of a barrel, you will find the maximum pressure is within an of inch of the chamber, so unless you are shooting a snub-nosed revolver, the pressure is already dropping by the time the bullet leaves the barrel. The effect has to be linear, given the same gun is used for all tests. Increase powder, increase max pressure, and increase velocity. I did not say that it is a one to one comparison, so the angle of the graph results are not necessarily a 45 degree line, but the line should be straight.
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