Wind Drift Calculator

Time of flight doesn't scale linearly with range because the bullet is continuously decelerating from drag — at longer ranges the bullet is traveling slower for the back half of its flight than the front half, so each additional 100 yards of range takes proportionally more time to cover than the previous 100 yards. Since wind drift accumulates with time of flight, not distance directly, this compounding effect is why drift grows noticeably faster than range at long distances, which is exactly why wind calls become dramatically harder past a few hundred yards.

Ballistic coefficient measures how well a bullet resists drag-induced deceleration, and a bullet that decelerates less stays closer to its vacuum (no-wind-effect) time of flight — meaning less lag time and therefore less wind drift, independent of any effect on bullet drop. A high-BC bullet and a low-BC bullet launched at the identical muzzle velocity toward the identical target will have different drop curves and different wind drift, because both depend on the same underlying quantity: how much time the bullet spends decelerating in flight.

Wind angle here is measured relative to your direction of fire, so 0° is a headwind blowing straight at you, 180° is a tailwind blowing from behind, and 90° is a pure crosswind blowing directly perpendicular to the bullet's path. A pure crosswind puts 100% of the wind's speed into sideways deflection, while a headwind or tailwind contributes essentially none to lateral drift (though they do slightly affect velocity retention) — angles in between split the wind speed between a crosswind component and a head/tail component using standard trigonometry.

Raw inches of drift only tells you the physical deflection at one specific range, but MOA (minutes of angle) and MIL (milliradian) are angular units that describe how far to dial or hold on your scope's reticle — and because they're angular rather than linear, the same MOA or MIL correction applies proportionally at any range once you've zeroed for it. This is why long-range shooters think and communicate in MOA or MIL rather than inches: 'hold 2 MIL left' is an instruction that works whether the actual target is at 400 or 800 yards, while '14 inches of drift' only describes one specific range.