Ke formula

TMCKEE

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Can anyone describe how you determine the loss of kinetic energy for shots at different distances? I know the basic kinetic energy formula, but it isn't the same at 10 yards vs. 60 yards. Is there a formula for this so that you don't have to chronograph at each distance?
 

AKDoug

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There are several balistics programs for archery out there. Unfortunately, the only free one that I knew about on the web..bowjackson.com.. is gone :( I use OnTarget, a program you have to purchase to calculate various balistic questions. The Ke number out at 60 yards really isn't really needed. My 60# bow shooting a 400 grain arrow makes 69 at 0 yards and only drops to 65 at 60 yards. Not a big deal to worry about. I have played with bows from 60 to 80 lbs and arrows from 300 to 600 grains and you never really see much beyond a change of 5 between 0 and 60 yards.
 

AKDoug

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There are several balistics programs for archery out there. Unfortunately, the only free one that I knew about on the web..bowjackson.com.. is gone :( I use OnTarget, a program you have to purchase to calculate various balistic questions. The Ke number out at 60 yards really isn't need. My 60# bow shooting a 400 grain arrow makes 69 at 0 yards and only drops to 65 at 60 yards. Not a big deal to worry about.
 

TMCKEE

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Thanks, I appreciate your help. I was just pondering the "how far is too far" question.
 

AKDoug

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Too far is too far ;) Too far is where you cannot hit with utmost confidence taking in consideration of the weather, the wind, the attitude of the animal, the ability of your equipment and your own personal ability. I doubt anyone can shoot far enough accurately where Ke comes into consideration.

I have personally killed an animal with a double lung shot at 50 yards. All conditions were perfect and I had utter confidence in my shot. I have competed on targets out to 100yard and while I can hit an animal kill zone at those distances I would never shoot an animal that far. 50 yards is pretty much my limit.
 

SusitnaAk

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Chart, You would still have to know speed of arrow,weight so forth.. its where you hit them, more than what you hit them with,Ive seen sharp broadheads from low poundage bows , 40lbs, Friends wife,Looked so slow, like you could run down there and grap that arrow right out of the air, watched it zip right thur both sides.
http://www.archeryhq.com/kin.htm
http://www.redhawk-archery.com/ke.php
 


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