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Calculate projectile muzzle kinetic energy in foot-pounds (ft-lbs) and Joules (E = 0.5 * m * v²), momentum, power factor, and terminal impact velocity.
Frequently Asked Questions
What is the ballistic kinetic energy formula for firearms?
In ballistics, kinetic energy in foot-pounds is calculated using: Energy (ft-lbs) = [Weight (grains) x Velocity (fps)^2] / 450,436. The constant 450,436 accounts for 7,000 grains per pound and standard gravitational acceleration (2 x 32.174 x 7,000).
What is the difference between kinetic energy and momentum?
Kinetic energy (0.5 x m x v²) increases quadratically with velocity, measuring potential tissue damage and hydrostatic shock. Momentum (m x v) increases linearly with velocity, measuring deep bone penetration and felt firearm recoil.
What is the USPSA / IPSC Power Factor?
Power Factor equals [Bullet Weight (grains) x Velocity (fps)] / 1,000. In competitive shooting, a power factor of 125 to 164.9 qualifies as 'Minor', while 165 or higher qualifies as 'Major' scoring.
How many grains are in one gram?
One gram contains exactly 15.4324 grains (and one avoirdupois pound equals 7,000 grains).