Basic Training: What Do the Numbers Mean on a Rifle Scope?

You may have noticed the numbers on a rifle scope. But what are they for?

The numbers on a rifle scope usually appear in a certain format like 4-12x40. Each number in this sequence represents a specific feature of the scope. In this example, the first set – 4-12x – refers to the magnification range.

Meanwhile the second number – 40 – is the objective lens diameter in millimeters. Both of these numbers work together to influence how you view your target, as well as the surrounding environment.

Understanding the numbers on your rifle scope can boost your accuracy while you improve your overall shooting experience. Let’s dig in deeper.

Magnification: The First Set of Numbers

The first set up numbers on your rifle scope reflect its magnification. But what is that?

Magnification determines how much larger an object appears in a scope compared to its view with the naked eye. In our example of 4-12X, the scope offers variable magnification. That means the magnification can be adjusted between 4 times and 12 times the actual size.

Lower magnification levels offer a wider field of view. That particularly comes in handy for close-range or moving targets.

Higher magnification, on the other hand, provides a detailed long-range focus. It’s essential if you want to aim for precision shooting at greater distances.

Most hunters prefer a balance of the different magnification levels. They might choose 3-9x, for example, since it gives them versatility in environments where targets might appear at various ranges.

Tactical and military operations, on the other hand, might require higher magnification so they can identify threats or targets over extended distances.

Objective Lens Diameter: The Second Number

What about the second number?

The next number on your rifle scope, such as the 40 in our example 4-12x40, is the diameter of the objective lens.

Now you may be wondering about the objective lens. It’s located at the scope’s far end, where the light enters the device. A larger objective lens allows more light into the scope for a brighter and clearer image. If you find yourself shooting in low-light conditions – like at dawn or dusk – a larger lens diameter can make a huge difference.

Larger lenses aren’t without their drawbacks, though. The larger the lens, the more weight it adds to the scope. That could pose a challenge in fieldwork that requires more mobility. As a result, shooters in law enforcement or military operations often prioritize compact scopes with smaller lenses. That lets them maintain their agility without sacrificing too much clarity.

Fixed vs. Variable Magnification

Some rifle scopes have a fixed magnification like 4x32. That means the scope has a single, unchanging magnification level. These sorts of scopes are simpler to use. They’re also usually lighter, which makes them a favorite for close-range shooting and in environments that require quick target acquisition.

Variable magnification scopes – like our 4-12x40 example – offer more flexibility. However, they also require the user to adjust magnification settings depending on their specific shooting scenario.

Recreational shooters often choose variable scopes for their greater versatility. These scopes let them adapt to both short- and long-range targets. Fixed scopes, on the other hand, more often appeal to hunters who are more focused on speed and simplicity.

Reticle Type and Its Impact

Now you know that the numbers on a rifle scope refer primarily to its magnification and lens diameter. But the reticle also plays an important role in terms of usability. Reticles, also known as crosshairs, help align your shot with your target.

Some common reticle types include duplex, mil-dot, and bullet drop compensator, also known as BDC. You need to understand your specific reticle so you can make the most of your rifle scope.

Mid-dot reticles, for instance, help with range estimation and wind correction. That makes them valuable when shooting long distances. Hunters, on the other hand, might instead favor BDC reticles since they account for bullet drops over different ranges.

Eye Relief and Field of View

The magnification of your rifle scope plays a role in the device’s field of view. What’s that?

FOV is the width of the area that’s visible through the scope at a given distance. Lower magnification offers a wider FOV, while higher magnification then naturally narrows it. A narrow FOV is preferred for precision shots, but a wider view helps shooters track moving targets.

Another important factor affecting rifle scopes and their efficacy is eye relief. This important factor refers to the distance between the shooter’s eye and the actual scope where they see the full image. Scopes with longer eye relief are usually considered safer for high-recoil firearms since they help prevent potential injuries. In fact, high-powered rifles often demand scopes with generous eye relief so they can be safely used.

Match Numbers to Applications

How do you choose the right rifle scope based on its numbers? You want to match the numeric labels to your specific shooting needs.

Hunters might go with a 3-9x40 magnification since it gives them more flexibility in forested areas and open fields. Law enforcement, on the other hand, might instead prefer a fixed 4x32 scope thanks to its rapid deployment in urban settings. Meanwhile, military personnel operating in diverse environments could require a more high-powered scope like a 6-24x50, which offers long-range precision.

Recreational shooters may even prioritize an affordable, lightweight scope with a balance of magnification and durability. When shooters understand how each feature supports their specific activities, it narrows down their options and helps them make a worthwhile investment.

More Than Mere Accessories

By now you’re well aware that rifle scopes are so much more than just accessories. No, instead they are precision instruments that are designed to improve accuracy.

Knowing your numbers on a rifle scope means you can better make informed decisions in the field and utilize your equipment to its fullest potential.

Whether adjusting your magnification to accommodate a shot from a distance or selecting the proper objective lens size for low-light conditions, the numbers of your rifle-and the features they relate to-will directly relate to performance.

Both experienced shooters and newcomers to the sport should be able to interpret the numbers on their rifle scopes for better results. Night Vision Guys offers a wide selection of rifle scopes that meet your specific needs. Whether you’re hunting, practicing at the range, or working in law enforcement, you’ll surely find the perfect scope that makes all the difference to maximize your shooting precision.