1. What is the Foot-Pounds Calculation?

The Foot-Pounds calculation converts velocity in feet per second (fps) to energy in foot-pounds (ft-lb) using the projectile's weight in grains. This is commonly used in ballistics to measure the kinetic energy of bullets.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• \( Weight \) — Projectile weight in grains
• \( Velocity \) — Velocity in feet per second (fps)
• 450240 — Conversion factor (2 × 7000 grains/lb × 32.174 ft/s²)

Explanation: The equation calculates kinetic energy by accounting for both the mass and velocity of the projectile, with appropriate unit conversions.

3. Importance of Foot-Pounds Calculation

Details: Foot-pounds of energy is a critical measurement in ballistics for determining stopping power, penetration capability, and compliance with hunting regulations.

4. Using the Calculator

Tips: Enter weight in grains and velocity in feet per second. All values must be valid positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why use grains for weight measurement?
A: Grains are the standard unit for measuring bullet and powder weights in ballistics (1 grain = 1/7000 pound).

Q2: What is a typical foot-pound value for hunting?
A: Most states require minimum 1000 ft-lbs for deer hunting, with larger game requiring more energy.

Q3: How does velocity affect energy?
A: Energy increases with the square of velocity, making velocity more significant than weight in energy calculations.

Q4: What's the conversion factor 450240 derived from?
A: It comes from 2 × 7000 (grains per pound) × 32.174 (standard gravity in ft/s²).

Q5: Can this be used for arrows?
A: Yes, though arrows are typically measured in grains for weight and fps for velocity, the same calculation applies.