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Education

Reloaders' Corner

Build better loads. Read the data. Stay safe at the bench.

Ballistic Terms — Plain English

Velocity (fps)

The speed of the bullet measured in feet per second, typically captured at the muzzle or a fixed distance.

Average Velocity

Mean velocity across a string of shots — the benchmark for load consistency.

Standard Deviation (SD)

Statistical measure of velocity variation. Lower SD = more consistent load. Sub-10 fps is excellent.

Extreme Spread (ES)

Difference between the fastest and slowest shot in the string. Indicates worst-case variance.

Power Factor

Bullet weight (grains) × velocity (fps) ÷ 1000. Used in competition classification.

Energy

Kinetic energy delivered downrange, measured in foot-pounds. Function of mass and velocity squared.

Doppler Radar Testing

Unlike a single-point chronograph, Doppler radar tracks the bullet through its entire trajectory — giving us velocity decay, drag coefficient, and downrange behavior. Every Fire Ammo lot is verified with radar-grade data before it leaves the bench.

  • Continuous velocity tracking from muzzle to target
  • Drag coefficient (BC) verification
  • Downrange energy retention modeling
  • Repeatable, lot-traceable measurements
Sample Velocity Decay — .308 168gr
DistanceVelocityEnergy
Muzzle2,650 fps2,620 ft-lb
100 yds2,480 fps2,294 ft-lb
300 yds2,160 fps1,740 ft-lb
500 yds1,860 fps1,290 ft-lb
700 yds1,590 fps940 ft-lb

Safety Disclaimer

Reloading involves inherent risks. The data, charts, and recipes referenced on this site are for educational purposes only. Always consult current published load data from reputable powder and bullet manufacturers. Start at the minimum charge, work up slowly, and inspect every component. Fire Ammo, LLC assumes no liability for use or misuse of this information.