1. What is Arrow FOC?

Front of Center (FOC) is a measurement that indicates how much of an arrow's total weight is located in the front half of the arrow. It's expressed as a percentage and affects the arrow's flight characteristics and stability.

2. How Does the Calculator Work?

The calculator uses the FOC formula:

Where:

• \( L \) — Total arrow length (inches)
• \( AMO \) — Balance point measurement from arrow nock (inches)

Explanation: The formula compares the actual balance point to the midpoint of the arrow to determine what percentage of the arrow's weight is forward of center.

3. Importance of FOC Calculation

Details: Proper FOC is crucial for optimal arrow flight. Higher FOC increases stability but may reduce speed, while lower FOC increases speed but may reduce accuracy.

4. Using the Calculator

Tips: Measure arrow length from nock groove to end of shaft (not including point). Measure balance point by finding where the arrow balances on a narrow edge.

5. Frequently Asked Questions (FAQ)

Q1: What is the ideal FOC percentage?
A: Typically 7-15% for most setups, with target archery preferring 10-15% and hunting setups often using 12-20%.

Q2: How does FOC affect arrow flight?
A: Higher FOC makes arrows more stable but slower, while lower FOC makes arrows faster but potentially less stable.

Q3: How can I adjust my arrow's FOC?
A: Add weight to the front (heavier points, insert weights) to increase FOC, or add weight to the rear (weight tubes, heavier nocks) to decrease FOC.

Q4: Does FOC matter for compound bows?
A: Yes, FOC affects arrow flight for all bow types, though the ideal range may vary between compound, recurve, and traditional bows.

Q5: Should I include vanes/fletching in FOC calculations?
A: The standard method uses just the shaft length and balance point, but some archers account for fletching in specialized calculations.