Tony Tello
Miembro de la Vieja Guardia
Valuing the Wind
Valuing the Wind
Having made an accurate wind speed estimate and determined the wind's direction, you now determine how this will affect your bullet's flight. First, consider the line between your muzzle and your target in the context of a clock, with 12 o'clock being directly to your front, six o'clock directly to your rear, and 9 and 3 o'clock being left and right respectively. (See the accompanying diagram.)
In this context, we first consider the wind's direction. If the wind is coming from 12 or 6 o'clock it has no value because it will not drift (push) your bullet right or left; it has no significant effect! Winds coming from 9 or 3 o'clock, however, have the greatest or "FULL" effect. It's the oblique winds, coming somewhere between those four primary directions - from, say, 10:30 o'clock or 4 o'clock - that can be the most perplexing because it only takes a slight direction change to significantly increase or decrease the wind's effect. A rough rule-of-thumb is that winds between the four primary directions are half-value, according to many sources; however, it has been my experience (borne out by data from Sierra Bullets ballisticians) that oblique winds halfway between FULL and No compensation are more deserving of a three-quarters value. These "oblique" angles are where wind estimation - or "doping the wind" - assumes as much art as science, and generates thoughtful discussions over adult beverages.
Valuing the Wind
Having made an accurate wind speed estimate and determined the wind's direction, you now determine how this will affect your bullet's flight. First, consider the line between your muzzle and your target in the context of a clock, with 12 o'clock being directly to your front, six o'clock directly to your rear, and 9 and 3 o'clock being left and right respectively. (See the accompanying diagram.)
In this context, we first consider the wind's direction. If the wind is coming from 12 or 6 o'clock it has no value because it will not drift (push) your bullet right or left; it has no significant effect! Winds coming from 9 or 3 o'clock, however, have the greatest or "FULL" effect. It's the oblique winds, coming somewhere between those four primary directions - from, say, 10:30 o'clock or 4 o'clock - that can be the most perplexing because it only takes a slight direction change to significantly increase or decrease the wind's effect. A rough rule-of-thumb is that winds between the four primary directions are half-value, according to many sources; however, it has been my experience (borne out by data from Sierra Bullets ballisticians) that oblique winds halfway between FULL and No compensation are more deserving of a three-quarters value. These "oblique" angles are where wind estimation - or "doping the wind" - assumes as much art as science, and generates thoughtful discussions over adult beverages.