Arrow FOC (Front of Center)
Standard Easton FOC formula from arrow length and balance point.
How this works
FOC compares where an arrow actually balances to where it would balance if its weight were spread perfectly evenly — its exact midpoint. The further forward the balance point sits past that midpoint, the higher the FOC percentage.
Why front-heavy arrows fly straighter
A higher FOC moves the arrow's center of pressure further from its center of gravity, similar to how fletching on a dart or shuttlecock stabilizes flight — it makes the arrow recover faster from any wobble off the string and resist steering from broadhead planing. That's the main reason hunting arrows, which need reliable broadhead flight, typically run a higher FOC than pure target arrows.
Frequently asked questions
What FOC percentage should I aim for on a hunting arrow?
Easton's own guidance puts hunting arrows comfortably in the 10–15% range, with some hunters going higher (15–20%+) specifically to improve broadhead flight and penetration.
Why does higher FOC help broadhead flight?
A more forward-weighted arrow moves its center of pressure farther from its center of gravity, which helps it recover faster from any wobble off the string — similar to how fletching on a dart stabilizes flight.
Does adding a heavier point always increase FOC a lot?
Yes, generally — since FOC depends on where the balance point sits relative to the arrow's midpoint, and the point is at the very front, even a modest increase in point weight shifts the balance forward noticeably.
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