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Energy/Velocity Retention<br>
What is EVR?<br><br>

The instant the pellet leaves the muzzle it begins losing velocity and kinetic energy to air resistance.
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Drag continuously retards the pellet until it arrives at the target. Retained velocity and energy are what it has left (retains) when it hits. It's only retained velocity and energy that really "count" and so are what we need to know when humane kills are the goal.
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This calculator predicts retained velocity and energy in both English and Metric units starting from muzzle velocity (typically measured with a chronometer) and the ballistic coefficient of the pellet.
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An "off-label" use of the Velocity Retention calculator involves back-correction for true muzzle velocity of chronometer readings made some distance from the muzzle. To use the calculator this way, enter the chronometer reading in the Muzzle Velocity window and the Range from muzzle to chronometer as a negative number. The "Retained Velocity" returned is then the actual muzzle velocity.
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Steve_in_NC
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