F.O.C.

Crossbow Hunting

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Hoagy
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F.O.C.

Post by Hoagy »

Is there a formula for calculating FOC?
Thanks, Hoagy
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Boo
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Re: F.O.C.

Post by Boo »

Some people just like stepping on rakes
Hoagy
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Re: F.O.C.

Post by Hoagy »

Thanks for the link Boo, altho after i posted this question this morning i found my answer on your website, imagine that :lol: .
F.O.C. % = 100 x (B-L/2)
.........................L
B = balance point (measured from the balance point to the rear of the arrow.)
L = arrow length
Measurements are in "Decimal Inch" (for example 13.3750")

Hope this helps other newbies, & i new i could count on you Boo
Thank You, Hoagy
Last edited by Hoagy on Thu Apr 19, 2012 11:50 am, edited 3 times in total.
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Boo
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Re: F.O.C.

Post by Boo »

One bit of advice. Don't get hung up on FOC. High FOC and greater offset do the same thing, give better guidance.
I never measure my arrow's FOC but Easton says 10 to 15% for hunting set ups.
Keep in mind that increasing FOC to correct a flight problem is actually masking the real issue which is fine as long as you understand that. Personally I would rather correct the real underlying problem rather than mask it.
Some people just like stepping on rakes
Hoagy
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Re: F.O.C.

Post by Hoagy »

Boo wrote:One bit of advice. Don't get hung up on FOC.
We'll remember that Boo, I just didn't know how to measure it which started my quest. :lol: Now i can move on to the next one.
Thanks, Hoagy
awshucks
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Re: F.O.C.

Post by awshucks »

There's an easier way to measure FOC. Measure arrow length and mark the middle, then mark balance point. On 20" arrows, it's 5% per inch, 4.5% on 22". Those are for the diffs in the two marks, btw.

I'm of the opinion that there are really only 3 FOC's, low[8-10%, med[11-15%, and high[16-xx%. Add to that, higher FOC's are good for fixed blade bheads, and can hide a lot of arrow probs.
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Boo
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Re: F.O.C.

Post by Boo »

awshucks wrote:I'm of the opinion that there are really only 3 FOC's, low[8-10%, med[11-15%, and high[16-xx%.
Well said Dan!
Some people just like stepping on rakes
Hoagy
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Re: F.O.C.

Post by Hoagy »

awshucks wrote:There's an easier way to measure FOC.
Hey Awshucks, thanks for the info, it came out the same as the formula for sure. And is easier! Now were gonna study Blazers.
Hoagy
awshucks
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Re: F.O.C.

Post by awshucks »

Hoagy wrote:
awshucks wrote:There's an easier way to measure FOC.
Hey Awshucks, thanks for the info, it came out the same as the formula for sure. And is easier! Now were gonna study Blazers.
Hoagy
Give the new AZ-EZ fletch tool a look while you are studying Blazers.................
"Eze 18:21"
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nchunterkw
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Re: F.O.C.

Post by nchunterkw »

Higher FOC makes the arrow flex less at impact which should help penetration, which is good for hunting. That is why I like higher FOC. It also helps stabilize an arrow by increasing the efficiency of the fletching by increasing the distance between the balance point and the fletches. Using shorter fletchings and moving them back on the shaft helps with stabilization as well.
Keith
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