Ballistic Coefficient

The Ballistic Coefficient calculator computes the Ballistic Coefficient a factor representing the effect of air resistance on a ballistic projectile.

INSTRUCTIONS: Choose units and enter the following:

• M- the mass of the projectile
• C_d- empirically derived value for the projectile
• A - the cross-sectional area of the projectile

Ballistic Coefficient (BC): The calculator computes the Ballistic Coefficient in units of kg/m².

The Math / Science

Ballistics is the science of mechanics behind projectile flight, behavior of objects during un-powered trajectories, and the effects of projectiles.  Ballistics predicts the flight of objects such as bullets, free-falling bombs, rockets, or similar objects whose path is determined primarily by gravity and air resistance.  The ballistic coefficient (BC) of an object defines the effect of air resistance on the object's flight. BC is inversely proportional to the negative acceleration of the ballistic object. The projectile, the ballistic object possesses drag, the BC measures the extend of the drag's effect on the object.

BC is a function of mass, diameter, and drag coefficient and also relates to the aerodynamics of the projectile. Ballistic coefficient has units of mass per area (lb/in² or kg/m²)

The formula for the Ballistic Coefficient is:

     `BC = M/(C_d*A)`

where:

• BC = Ballistic Coefficient
• M = Mass of Projectile
• C_d = Coefficient of Drag
• A = Cross-sectional Area of Projectile

Firearm Calculators

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