FOC Questions

Ezbagr · 10-04-2009, 04:16 PM

Just wondering what everyone is shooting as far as FOC goes while shooting broadheads. The reason I am asking is because I am shooting 29 inch Easton ST Axis arrows And if I put a Muzzy 100 grain head on here is my calculation-
30.5 inches-Arrow over length-bottom of knock to tip of broadhead
15.25-center of arrow
13-balance point in inches from tip of broadhead
Calculation is 15.25-13=2.25
2.25 divided by 30.5=07.3 percent
This seems pretty low to me.
I checked FOC again using a 160 grain field point-the following numbers are
30 inches-OAL
15 inches center
11 inches-balance point
FOC calculation comes out at 13.3
If the previous calculation was done using a 160 grain broadhead the FOC would have dropped to 12.2 due to the broadhead being longer than the field point.
I do find these numbers pretty interesting since I believe that there are alot of people shooting 100 grain heads with simmilar arrows that I use. I have read where FOC should be around 10 percent with broadheads.
I would really like to be up to the 12 percent number but that would require shooting a pretty heavy broadhead.
Any comments would be greatly appreciated.

10-04-2009, 05:23 PM

For trad setups I won't shoot under 14%. For compounds anything over 8 or 9 work.

TFOX · 10-04-2009, 08:00 PM

It is recomended to be between 10-15% foc BUT that is not measured to the end of the broadhead,but to the end of the shaft from the nock groove.

If you still don't like your foc measuring this way,feathers will bring the foc up.

I believe I am at 13% right now.

I believe will be going to the 20% range next year .

ijimmy · 10-07-2009, 07:17 AM

Quote:

Originally Posted by TFOX

It is recomended to be between 10-15% foc BUT that is not measured to the end of the broadhead,but to the end of the shaft from the nock groove.

If you still don't like your foc measuring this way,feathers will bring the foc up.

I believe I am at 13% right now.

I believe will be going to the 20% range next year .

True, the part of the arrow that flexs is what you want to measure , Im a fan of high foc's nowadays at least 10% , more better between 12 and 20