Stability Terms

Input Data

BarrelTwist
Length of one turn of the barrel rifling. For a 10" twist barrel, enter 10 inches.
Bullet Weight
The weight of the bullet.
Bullet Length
Total length of the bullet.
Plastic Tip Length
Length of the plastic "ballistic tip" if it exists. Otherwise zero.
Caliber
Diameter of the bullet.
Muzzle Velocity
The velocity of the bullet as either (1) measured at some distance from the muzzle or (2) as estimated from reloading data. The on-line ballistics page can correct for the distance to chronograph. (The velocity lost traveling to the chronograph.)
Pressure
The absoluate barometric pressure.
Temperature
The measured or estimated air temperature.

Output Data

Stability
The Miller stability value. It should be between 1.3 and 2.0 to ensure stabilty (the military uses 1.5).