Arrow/Broadhead Penetration Education


PotashRLS

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This should make great reading for all the bowhunters gearing up for the upcoming archery seasons. A lot of threads go around annually about arrow/broadhead penetration, kenetic energy and light vs. heavy arrows. This is some technical reading but you will come away with the scientific answer to many questions. I hope you all enjoy it.

Oh and have a calculator handy too! ;)

http://rds.yahoo.com/_ylt=A0LEVIYrxZ1KtfoAbRIPxQt.;_ylu=X3oDMTExN3Y1YzI1BHNlYwNzcgRwb3MDMQRjb2xvA3JlNAR2dGlkAwRsA1dTMQ--/SIG=13nf73lie/EXP=1251940011/**http%3A//www.tradgang.com/ashby/Momentum%2520Kinetic%2520Energy%2520and%2520Arrow%2520Penetration.htm

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  • 4 weeks later...

Great article.....Just give it a change b/c it's a little wordy....

Here's my Kenetic Energy...

11.3 GPI arrow at 28.25 inches...100gr broadhead and 12 gr knock....

431.225/2=215.6125x276fps=

59,509.05x276=16,424,497.8/225218=

72.927 kenetic energy(foot lbs)

I thought about switching to this before I got this data....

8.3 gpi arrow...us

346.475/2=173.2375x292=50585.35x292=

14,770922.2/225218=

65.584 Kenetic Energy(foot lbs)

So here's the ultimate question that everyone must answer. For me is 16 FPS worth losing 7.4 foot lbs of energy?

another thing that needs to be noted is that my arrow drop is the same with both arrows in 10 yard increments. So the drop from my heavy arrow from 20-30 is the same for the lighter arrow from 30-40....The lighter arrow gains me 5 extra yards before drop from 20 to 25.

Simple answer I'm not switching....

Also great notes about expandable broadheads and failure rates and what it does to a arrow's energy on impact....

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Yes that works for KE but doesn't elaborate on Momentum. Try this link if the others don't work.

http://www.booneman.com/_terminalarrow.php

maybe I read it incorrectly but it seemed to focus on factors outside KE in regards to arrow performance. I.E. why bow companies focus on KE instead of momentum and other factors because the true numbers show that lighter arrows have to fly so much faster to acheive the same results as a heavier arrow.

Long story short it says that a lighter arrow actually hurts you when it comes to penetration as compared to a slightly heavier arrow out of the same bow....

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If I am reading your post correctly Hoosier, you are shooting about a 430 grain arrow/broadhead at 276 fps. If that is so you have a kinetic pulse of about 1219. You need a minumum KP of 500 to penetrate a deer shoulder bone. (not kinetic energy).

Penetration is more a factor of momentum which is affected by arrow mass more so than arrow speed.

Dr. Ed Ashby's reports explain it way better than I can. You can find them at www.tradgang.com.

I used to shoot a 415 grain arrow at about 250 fps. That gives a KP of 853. I now shoot a 590 grain arrow at about 210 fps. That is a KP of 1022. Thats about a 20% increase in penetration.

I think the best setup for most whitetail hunting is a fast, heavy arrow. Like a 600 grain arrow at 250 fps. Many people don't consider that fast, but I do, and it will penetrate.

Prepare your setup for worst case scenarios, not best case. I read that and now believe in it.

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I think the best setup for most whitetail hunting is a fast, heavy arrow. Like a 600 grain arrow at 250 fps. Many people don't consider that fast, but I do, and it will penetrate.

Prepare your setup for worst case scenarios, not best case. I read that and now believe in it.

I whole-heartedly believe this!!!!

I still shoot Aluminum Easton XX78 Super Slams. They are just under 30" long and weigh 550grs with the Grim Reaper Broadhead. I shoot them between 255 and 260fps on average. This setup clearly helped me harvest my bear this past week as my arrow went through the shoulder blade, shattered the spinal column and rested under the ribs on the other side. All this with an expandable which held together very well. Two blades were still intact and straight and one actually sheared off in the middle instead of bending. That blade was found inbetween two vertebraes. I am very please with the outcome.

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