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2050z
03-17-2010, 11:10 AM
:confused:

Mike Javi Cooper
03-17-2010, 11:19 AM
Here..

atombomb
03-17-2010, 11:21 AM
so would that be 10% FOC in the pic, or 20%

2050z
03-17-2010, 11:23 AM
http://archeryreport.com/calculators.html i found this.

JBS
03-17-2010, 11:26 AM
Here is Goldtip's online cal.

http://www.goldtip.com/calculators/foc.asp

RickBarbee
03-17-2010, 11:34 AM
Timm the balance point is 3" in front of the center mark. 3" is 10% of 30", so 10% FOC.

If the balance point was 5" in front of center it would be 16.67% FOC.


Hope that helps.

huntinpool
03-17-2010, 02:39 PM
# of inches front of center divided by total length of arrow

redneck82
03-17-2010, 03:19 PM
Pardon my ignorance, but what does that tell you in regards to the arrow?

What makes this info useful?

cwbow
03-17-2010, 03:25 PM
Pardon my ignorance, but what does that tell you in regards to the arrow?

What makes this info useful?

x2

3children
03-17-2010, 03:33 PM
This info is for those of us that want to pull the chain, not push it! LOL FOC or forward of center pull the arrow thru upon impact, if you try pushing it the arrow will bend or break and the energy is lost. For hunting you want 10-15% foc, I like more so I use 18%
1)measure end to end
2) divide that number by 2
3)Subtract that number by the new center balance
4)Multiple that number by 100
5)Take that number and divide it by arrow total length

Ellis
03-17-2010, 03:38 PM
This info is for those of us that want to pull the chain, not push it! LOL FOC or forward of center pull the arrow thru upon impact, if you try pushing it the arrow will bend or break and the energy is lost. For hunting you want 10-15% foc, I like more so I use 18%
1)measure end to end
2) divide that number by 2
3)Subtract that number by the new center balance
4)Multiple that number by 100
5)Take that number and divide it by arrow total length

So FOC is for how the arrow acts upon impact, right. Basically you want the front of the arrow to have more weight distributed to it so that the front of the arrow drives through instead of the weight being in the rear of the arrow and flexing upon impact. I'm new at this and just confirming that is what I read.
So, the higher the FOC the better penetration?

VorTexan
03-17-2010, 03:50 PM
Listened to Dr. Ed Ashby at the ATA and his demonstration on FOC was more than interesting. He did at demonstration using a lead pencil with fletching, a nail, and a pencil with an extreme FOC (large eraser on front). He shot all of them using a rubber cord to demonstrate not only flight distance but accuracy as well...this doesn't include the penetration factor. As stated above pulling or pushing...which allows you to do more? Go to www.alaskanbowhunter.com and you can read more. Ed likes 19 FOC or greater....I did say greater!

huntinpool
03-17-2010, 06:46 PM
This info is for those of us that want to pull the chain, not push it! LOL FOC or forward of center pull the arrow thru upon impact, if you try pushing it the arrow will bend or break and the energy is lost. For hunting you want 10-15% foc, I like more so I use 18%
1)measure end to end
2) divide that number by 2
3)Subtract that number by the new center balance
4)Multiple that number by 100
5)Take that number and divide it by arrow total length

Simplified - measure the difference from true center and balance point. Divide that by total arrow length with a calculator and move the decimal point to spaces right. Alot less math.

Zen Archery
03-18-2010, 12:23 AM
Bow Jackson (http://home.att.net/~sajackson/archery.html)

Second Tab on left.