Understanding rifle scope magnification vs distance is critical for making the right choice of scope for your needs. You’ll be a much more effective hunter once you can grasp this relationship and use it to your advantage during your hunts.
The relationship between magnification and distance becomes fairly straightforward once you understand how scope magnification works. Rifle scope magnification involves two numbers, one of which refers to the magnification and the other of which identifies the objective lens diameter. So, if you have a scope that is 6.5 x 50, it would mean the magnification is 6.5x and the objective lens diameter is 50 mm. There are also variable magnification scopes, which will have a range as the first number.
Scope magnification is defined by various properties of the lens, including the curvature, thickness, material, coating, and diameter. Once these properties are known, the magnification can be determined. The lens inside a magnified scope serves three purposes, which are to magnify the target, invert the magnified image, and focus the image so that it’s recognizable in the right position by your eye. It’s important to understand the object viewed through the scope is just an image of the real thing.
The magnification number defines the ratio between the image you see and the actual object. In other words, the magnification number tells you how the image you see through the lens differs from the real target. For instance, if you have a 6x magnification scope, the image you see is six times closer than the actual object. If the target is 60 yards away, it will appear to be 10 yards away through your magnified scope.
As the magnification increases, the image you see will appear to be closer, so if you double the magnification from 6x to 12x, the apparent distance will be twice as close, or five yards away. Additionally, magnification has an effect on the apparent height of the object so that the target will appear larger as it’s magnified, as well as closer. As such, magnification is both linear and proportional, so you can easily predict the outcome of variable magnification scopes.
The most obvious advantage of a magnified scope is that you will get a clearer sight image than with your naked eye, allowing you to shoot more accurately even at great distances. You won’t have to get as close to your prey as you would without a magnified scope. You’re also increasing safety as well, since you’ll be able to see what’s behind your target through the scope, ensuring you have a clear path to shoot.
You’ll also be able to hunt in lower light conditions with a magnified scope, as they are designed to collect available ambient light to illuminate darker areas for longer. Precision is yet another advantage of magnified scopes, as you’re able to better pinpoint your shot when the target appears closer to you. Traditional iron sights have a margin of error of 6 inches, but a magnified scope has a margin of error of 1/8th of an inch at 100 yards.
There are few drawbacks to using magnified rifle scopes when you’re hunting, but there are some limitations to their effectiveness, especially in terms of distortion. These trade-offs should be considered when you’re shopping for a magnified scope to determine which limitations you can live with.
Fringing, which is also known as chromatic aberration, is something that is present with every lens but will worsen as the magnification increases. With this distortion, you’ll see a rainbow through the lens, which can interfere with your view of the target. Without correction for fringing, the image may be blurry or fringed in purple.
In low magnification scopes, field curvature will make the edges of your target appear blurry, while the focal point is sharp and clear. This is because the lens is curved and causes you to view the target through more of a sphere than a plane.
As you increase the magnification of your scope, you’re more likely to run into a spherical aberration, which is when the light from the edges of the lens hits a different focal point than the light that passes through the center of the lens. It occurs because the light at the edges is bent more than the light in the center. You’ll notice that as with field curvature, the edges of your target are blurrier than the center.
You can calculate the field of view you’ll get with a scope by dividing the objective lens diameter by the magnification. You’ll see that as the magnification increases, your field of vision will shrink in proportion because the diameter is a fixed number. Essentially, this just means that you’ll be able to see less area surrounding your target as your magnification increases.
The more lenses you have in your scope, and the thicker they are, the less light the scope will transmit. Instead, light will be reflected or absorbed, which means the image will be dimmer with these scopes than with ones that have fewer or thinner lenses. Additionally, higher magnification scopes automatically have thicker lenses, which means they will produce a darker image overall.
The scope you choose should have as little magnification as possible for you to hit your target. This means that more magnification isn’t always better, especially when you factor in the various distortions that are inherent with magnified lenses. Most hunters find that they don’t need more than 10x magnification at 500 yards, and many shooters will settle on between 4x and 6x magnification for recreational hunting. Most targets during hunting season will be between 100 and 200 yards away.
Hunters almost always want at least some magnification for their rifles because it increases their accuracy and makes hunting safer. Consider the various distortions that come with magnification so you can determine how much magnification you need for your purposes.