Preview – Death From Above
Photography by Kenda Lenseigne
Shooting Offhand Getting Too Easy? How About Climbing Aboard a Helicopter for a Low-Altitude Strafing Run?
Once the preserve of the military or the ultra-rich, shooting from a helicopter has become more mainstream in the past few years. Several competitions have featured helicopter stages in the main match, crazy Uncle Ted filmed a dubious TV series about aerial hog hunts, and Magpul’s video on the subject has been flying off the shelves (pun intended). We decided to examine the subject and the unique marksmanship challenges it poses, so that should you hopefully get the chance to take to the skies, you’ll have an idea of what you’re getting yourself into.
Ballistically speaking, there are a number of factors to consider when shooting from the door of helicopter moving at 85 knots. We all know that wind will affect our bullet path significantly, but at short range and under normal conditions wind can mostly be ignored. “Normal conditions” generally assumes the type of wind speeds encountered on the range — let’s face it, unless we really need to be behind a rifle for our job, most of us will pack up and go home as soon as the wind hits 15 mph. That 85-knot airspeed translates to a Category 2 hurricane, which is decidedly outside the norm.
With this kind of crosswind, bullets start doing strange things. Because they’re stream-lined projectiles, the tip will move into the wind and the base moves downstream, introducing significant yaw and affecting terminal performance. The “Magnus effect” comes into play where, due to the bullet’s spin, an up or downward force is applied, depending on whether the wind is coming from the right or left. Assuming a right-hand rifling twist, if you shoot from the left side of a moving helo, your bullet will impact low. Shoot from the right side of the bird and it’ll hit high. Just how high or low the bullet will impact depends on how perpendicular the target is from the aircraft — think of it as full or half value wind (i.e. “full value” denotes when wind is blowing in a direction exactly perpendicular to your bullet’s path, imparting full effect on pushing it right or left, whereas “half value” refers to wind blowing at a 45-degree angle, thus affecting it less). And if the target is static and you’re moving, this angle will constantly change.
Now add in Newton’s first law. Assuming a muzzle velocity of 2,800 feet per second (fps), our bullet will take about 0.12 seconds to cover 100 yards. If we’re shooting at a target 90 degrees to our direction of travel, at 85 knots the bullet also has a sideways velocity of around 150 fps, which translates to a whopping 18 feet at 100 yards. Aim directly at your target, and the bullet will hit that far in front of it. Which means that if you’re used to automatically leading a moving target, you’ll have to reprogram that part of your brain.
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