Experiments

How Shooting a Target Works

posted: 04/11/12
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Whether you hurl, sling, throw or shoot an object, the physics of ballistics will come into play. Ballistics simply refers to the study of projectiles, and knowing more about it will help us understand how to accurately hit a target.

Standing Your Ground

One basic rule of physics states that for every action, there is an equal and opposite reaction. This is why, when you shoot a gun, it will produce a kickback (or recoil) and push back toward you. This can alter your aim, which requires you to reset your position each time you fire at your target. To reduce this effect, it's good to attain as much stability as possible with your stance. If you're shooting a rifle, this will mean steadying the butt of the weapon at your shoulder and holding the barrel with your nontrigger hand. No matter what type of gun you're shooting with, it's important to find a natural stance and to consider how your muscles relax while you fire.

Straight Shooting

Once the bullet leaves your gun, it's subject to multiple forces, which are studied under the realm of external ballistics. You may think you have no control over the bullet after it leaves the gun, but knowing about these forces will help you work with them to achieve accuracy.

Although many imagine a bullet's trajectory to be a straight line, it's not. Especially across long distances, a bullet will fall significantly due to gravity. Gravity affects a speeding bullet at the same rate as any other falling body. In other words, if you dropped a bullet from the height of a gun at the same time you fired a bullet from the gun horizontally in a level, open space, the two bullets would land on the ground at the same time. This is why (unless you shoot straight up or straight down) it's impossible to literally be a straight shooter. You've got to consider gravity, especially in long, horizontal shots. Despite what many think, shooting a target at an angle (uphill or downhill) reduces the affect of gravity over a distance because it shortens the horizontal component of the trip.

Focus Your Sights

Because our sight works much differently than a bullet in the air, we need to understand how to adapt it. For instance, although a bullet forms a parabolic trajectory in the air, our line of sight is straight. Looking through a scope at the top of a rifle, our line of sight can intersect the bullet's arc trajectory only twice. Ideally, the target, line of sight and trajectory will intersect.

In addition, our sight is limited in terms of focus. It's physically impossible for us to focus through the gun and on the distant target at the same time; the shooter must choose to focus on only one.

Bouncing Bullets

Another important thing to consider when aiming for a target? The possibility of ricochet. The potential for ricochet depends on many factors, including the angle of incidence (angle at which the bullet hits a surface,) the surface material, as well as the velocity, shape and construction of the bullet itself. Any material -- even water -- can cause a bullet to ricochet when it strikes at the right angle. However, the critical angle (under which the bullet will ricochet) is larger with materials like steel, making this a dangerous material to shoot at -- think Ralphie in A Christmas Story. So if you remember the physics involved, you'll hit your target without shooting your (or anyone else's) eye out.

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