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Calculate ballistic coefficient (BC) from bullet weight, diameter, and drag model. Compare G1 and G7 BC for long-range shooting trajectory.
Calculate bullet drop, windage, and trajectory from muzzle velocity and distance. Solve elevation and wind holds for rifle shooting.
Energy equals one-half mass times velocity squared. Use bullet weight in grains and velocity in fps for ft-lbs result.
Energy (ft-lbs) = (weight gr × velocity² fps) / 450,400Energy decreases as velocity drops from air drag. Retained energy at range requires velocity at that distance from trajectory solver.
E_downrange = (weight × V²) / 450,400Metric energy in joules: multiply grains to grams, fps to m/s, apply ½mv².
Joules = (weight gr × 0.0648 × velocity fps × 0.3048²) / 2Updated: July 2026
Energy = (100 × 2960²) / 450,400 ≈ 1,945 ft-lbs. Adequate for deer at moderate ranges with proper bullet construction.
Energy = (124 × 1150²) / 450,400 ≈ 364 ft-lbs. Typical self-defense load — energy alone does not determine terminal performance.
Energy ≈ 4,260 ft-lbs. Large bore African game cartridge — retained energy at 200 yards still exceeds 3000 ft-lbs.
Energy at the animal matters, not at the muzzle. Calculate retained energy at max hunting range using trajectory data, and select bullets designed for game size.
Cast bullets and some handloads vary ±2–3 grains from nominal. For energy calculations within 5%, nominal weight is fine; for precision, weigh bullets.
Muzzle energy quantifies a bullet's kinetic energy at the muzzle — a key metric for hunting adequacy and cartridge comparison. This calculator computes ft-lbs and joules from bullet weight and chronographed velocity.