1. What is FOC (Front of Center)?

FOC (Front of Center) is a measurement used in archery to describe the balance point of an arrow. It represents the percentage of the arrow's total length that is in front of the center point.

2. How Does the Calculator Work?

The calculator uses the FOC equation:

Where:

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

Explanation: The equation calculates what percentage of the arrow's length is in front of the exact center point.

3. Importance of FOC Calculation

Details: Proper FOC affects arrow flight stability, accuracy, and penetration. Most target arrows have FOC between 7-15%, while hunting arrows typically have higher FOC (10-20%).

4. Using the Calculator

Tips: Measure total arrow length (L) from nock groove to tip. Measure balance point (AMO) from nock end to where arrow balances. Both measurements should be in inches.

5. Frequently Asked Questions (FAQ)

Q1: What is the ideal FOC for target archery?
A: Typically 7-15%, but depends on arrow setup and archer preference. Lower FOC provides faster arrow speed, higher FOC improves stability.

Q2: How does FOC affect arrow flight?
A: Higher FOC makes the arrow more front-heavy, improving stability in flight but reducing speed. Lower FOC makes arrows faster but potentially less stable.

Q3: How do I measure balance point accurately?
A: Use a narrow edge (like a pencil) to find where the arrow balances perfectly. Measure from nock groove to this point.

Q4: Does FOC affect broadhead tuning?
A: Yes, higher FOC often helps broadhead-tipped arrows fly more accurately as it keeps the point forward during flight.

Q5: Can FOC be too high?
A: Yes, excessive FOC (>20%) may cause arrows to plane or porpoise, and can reduce kinetic energy at the target.