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Arrow FOC
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Front of Center (FOC) measures how front-heavy your arrow is. Most hunters target an FOC over 10%, with higher setups delivering better penetration on big game. Enter your components below for an instant reading.

Your Arrow Components
Measured from insert to nock groove
Find on manufacturer spine chart (e.g. 8.5)
Field tip, broadhead, or judo point weight
Typically 10–20gr for standard inserts
3× Blazer ≈ 18gr, 3× Raptor ≈ 24gr, feathers vary
Standard nock ≈ 9–12gr, lighted nock ≈ 20–30gr
Your Results
FRONT OF CENTER
11.5%
Medium
Total Arrow Weight385 gr
Balance Point from Tip10.98"
Grains Per Inch13.5 GPI
FOC REFERENCE
< 7%Too Low — poor flight stability
7–10%Low — functional for most target shooting
10–15%Medium — where most hunters land
15–20%High — excellent penetration on big game
> 20%Ultra-High — dedicated deep penetration builds

What is FOC and Why Does It Matter?

Front of Center (FOC) is the percentage of your arrow's length that lies in front of its balance point. A higher FOC means more mass forward — like a dart — which improves stability in flight and penetration on impact.

Most hunters target an FOC over 10–15%. For big game, high-FOC setups (15–20%+) are increasingly popular for deep penetration through heavy bone and for pass-through shots at distance.

The easiest ways to increase FOC without changing your spine:

  • Increase point weight (100gr → 125gr → 150gr)
  • Use a heavier insert (standard → brass/stainless)
  • Shorten your arrow length slightly
  • Use lighter vanes (switch from 40gr feathers to 18gr vanes)
  • Use a lighter nock (avoid heavy lighted nocks for high-FOC builds)
Ready to Build the Exact Setup?

Configure your arrow in the 3D builder — your FOC updates live as you pick components.

Open the 3D Builder →