JMR40-You bring up some valid points. I think what most likly is happening is as you state-The bullet is going faster,not because the crohny is faulty but because out side temp is causing the bullet to go faster. The same load shot on a 40 degree day will shoot hotter and faster on a 90 degree day. The chrony is just simply showing you the difference temp can make. I know some bench shooters that will set there ammo in the sun shine before a match to heat them up and i also know some that will keep them in the shade.
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