Quick Answer
Wind drift is a concern when shooting at long distances with the .17 HMR, as its flat trajectory can be greatly affected by crosswinds.
Understanding Wind Drift
When shooting at long distances, even a gentle crosswind can cause the bullet to drift off-target. The .17 HMR has a relatively low ballistic coefficient, which makes it more susceptible to wind deflection. For example, a 17-grain Varmint Express bullet fired from a rifle at 4000 feet per second can drift 1.8 inches off-target at 400 yards with a 5 mph crosswind.
Calculating Wind Drift
To estimate wind drift, hunters can use the following formula: wind drift (in inches) = 10.8 x (bullet weight in grains) x (muzzle velocity in feet per second) x (crosswind speed in mph) / (1000 x range in yards). For the .17 HMR, this simplifies to approximately 1.8 x (bullet weight in grains) x (crosswind speed in mph) / (1000 x range in yards). For example, at 400 yards with a 10 mph crosswind, a 17-grain bullet would drift approximately 8.4 inches.
Mitigating Wind Drift
To compensate for wind drift, hunters can adjust their aim in the direction of the crosswind. The amount of drift can be estimated using the wind drift formula and applied to the target. Alternatively, hunters can use a chronograph to measure the muzzle velocity and a ballistic calculator to estimate wind drift and range corrections. This can be especially useful when shooting at long distances or in windy conditions.
Find more answers
Browse the full Q&A library by topic, or jump back to the topic this question belongs to.