Front of Centre Question

[JohnK]

I would say as high as possible without making your arrows take a dive beyond 70m. This is especially important for lanky archers like us, who have a hell of a lot of arrow to steer through the wind.

(Out of interest, what draw weight are you shooting with those X10s? Thanks )

[tel]

looking at the two calculators mentioned earlier, one (Mr.Bs) appears to include the pile in the length for calculation whereas the other does not - is this an anomaly to do with one taking the balance point as a distance from the point and the other from the groove, or am I reading it wrong and does Mr.B intend the point to be read as 'the end of the shaft'?

[pHz]

maybe gather some rough figures to see what people are actually using ?

28" cartel x-perts (820 spine but not sure thats relevant) with 110gn piles - FOC comes out at 12.5%

zoe has 25" ACCs (3L-04) with 100gn piles and an FOC of 16%

slainte : rob

[archery_mum]

For target I work on 14 - 15% FOC

[NoAngel]

Does it make any difference if you are Recurve or Compound? I would have thought as Compound arrows fly with a flatter trajectory, they could get away with a lower FOC percentage?

For myself I am talking about Recurve archery.

[King Custard]

14.8% on my ACE's - I believe Easton recommend 11 to 15% for ACE's.

I was under the impression that an Overly High FOC led to 'tail wobble', though I've never tested this out

[BorderBows]

We would say as far forward as possible without adding too much mass to the arrow.
Too much mass will slow things down too much and the sightmarks will suffer at the longer shots, if your not struggling with that, then the more the better.
A heavy skinny arrow should suffer less side effect from wind.
more FOC will need a higher spine due to the difficulty in pushing that heavy point. So tune is more important than FOC, but try your best to get it up front....
Thats our 2cents worth.

It works for Cross bows.

[tel]

...but can anybody tell me why the two systems highlighted before are different?

[NoAngel]

Well I have just worked out my FOC and its is 13.5% so I recon that's right on the ball. To get it any higher I would have to use 120 points which make the arrows to weak (or I could just remove the fletchings and nock ).


Found this link although there is a small typo in the formula, should be :

F.O.C. % = 100 x (A - L/2)

--------------

L

SoCal Archery Link

NOTE: This is measure to the end of the shaft, not the point.

I also found this which says for A/C/Es.

"The recommended insert + point weight gives a 12-15% F.O.C. balance with Spin-Wing Vanes and 11-14% F.O.C. balance with plastic vanes."

Hope its of some help to others.

NA