Bullet Stability Factor and
Spin Drift Calculations and Corrrections
Spin Drift calculations first require that a Bullet Stability be calculated.
Clicking on the 
button will calculate a Bullet Stability Factor.
The generally accepted minimum bullet stability factor value is 1.5.
The generally accepted SAFE bullet stability factor value is 2.5
The required variables to calculate a bullet stability factor are:
Clicking the 
Query button will display the information box detailing the required entries.
Once the Bullet Stability factor has been calculated, check the 
Spin Drift Calculation checkbox to enable trajectory spin drift and sight compensation calculations to be performed when the 
button is clicked.
The stability factor and the time of flight to each range will then be used to calculate the right hand rotational spin drift of the bullet at each range.
The drift (in inches) value will be included in the Ballistics and Trajectory table under the heading of "Right Drift In Inches"
The sight correction values needed to compensate for the spin drift at each range will be included in the Sight Settings table under the heading of "Correction Graduations".
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