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pupper
04-15-2007, 08:24 PM
so what are the advantages of having a higher or lower front of center?

is there any disadvantage of having a higer FOC?

what are some of the hunters on the site FOC calculation?

go here to find out: http://www.goldtip.com/calculators/foc.asp

my current setup has my at 10.93% FOC. can this be improved? should it be?

if I switch to g5 nocks and inserts I will be at 10.86% FOC but shooting a lighter arrow by 11 grains.

also has anyone researched the new Maxima hunter arrow that has a emphasis on FOC?

here is the site:http://www.carbonexpressarrows.com/index_2_hunter.shtml

thoughts anyone???

Bow Walker
04-15-2007, 10:06 PM
F.O.C. (Front Of Center)....... Consider this excerpt from a 5 chapter discourse on arrows...

"....A projectile's flight is most stable when most of the projectile's mass is positioned Front of Center (FOC). As such, an arrow should be heavier in the front than in the back."

"With that said, it is generally believed that an arrow with a high FOC will fly well, but with premature loss of trajectory (nose-diving). While an arrow with a low FOC will hold it's trajectory better, but it will fly erratically. So again, another trade-off for you to consider.

While there doesn't seem to be a magic number to aim for, it is generally agreed that the optimal FOC balance for an arrow is somewhere between 7% and 15%. In the example on the left, the 30" long arrow has balance point that is 3" forward of the arrow's actual center (15"). So it's FOC is 3/30 or 10% - a reasonable FOC balance. So when you order your custom arrows, keep FOC in mind. If you choose heavy 5" vanes and an anorexic 50-grain tip, you'll likely have an FOC that is too low. On the other hand, if you choose 3" lightweight feathers and a jumbo 175-grain tip, you'll likely have too much FOC. Choose an arrow setup that will give you an FOC balance of roughly 7-15%"



Hope this sheds some light on the subject for you?

pupper
04-15-2007, 11:48 PM
thanks alot for the info,

I was wondering what the trade off was for going with a heavier FOC.

So Bowwalker, what do you think of those maxima hunter arrows that have more FOC weight? did u go to the web site?

Bow Walker
04-16-2007, 10:17 AM
Pupper......
I think that I'd rather build my own and thereby control the F.O.C. with my own components.

Having said that - I haven't tried those shafts and without doing so, I won't knock them or endorse them. I'd like to 'play' with some to see exactly what's going on first.

The idea seems to have merit, but there are some questions that come to mind. Exactly how much "weight forward"? How does it affect the spine throughout the length of the shaft? Things like that.