Bullet Trajectory

The calculations used here were copied, via the Web Archive, from a defunct web site. Despite their simplifications, especially for drift, the results are close enough to those from JBM and QuickTarget to be useful, and the calculations are done by the browser instead of on a server.

Velocity BC Weight
Sight height Zero at Elevation
Wind speed Wind angle Temperature Altitude
Range Interval


Velocity       at muzzle               fps    4400 or less
BC             G1 ballistic coeffient        .005 or more
Weight         of bullet               gn     10 or more

Sight height   above bore center       in
Zero at        path crosses sights     yd
Elevation      bore, from horizontal   deg    up to +/- 60

Wind speed                             mph
Wind angle     to barrel               deg    0 is downrange, 90 is direct crosswind
Temperature    air                     F
Altitude       above sea level         ft

Range          of last output          yd     1000 or less
Interval       spacing of output       yd     5 or more

Outputs at each Interval

Range, yards
Velocity, fps
Rise from line of sight, inches
Drift from line of sight, inches
Time of flight, seconds
Energy, foot pounds