Rifle Optics: Scopes

Last Updated on April 7, 2023.
Rifle Optics Scopes

A rifle scope is a type of weapon sight that uses a series of lenses to allow you to see a magnified image of your target. Scopes come in various configurations, from reticle design and magnification to ergonomics and weight. But which should you buy for your rifle?


Optical Choices

Shooters today have an almost endless selection of optics to choose from. Traditional iron sights are reliable and proven. Reflector/holographic sights are fast. But when you need to see your target far away, the rifle scope is king.

A rifle scope magnifies the target, allowing you to positively and clearly identify it as the range increases. In addition, a rifle scope also magnifies your perception of the rifle’s movement. This helps you determine the extent to which you need to adjust your shooting position, stock weld, breathing, and trigger control to achieve an accurate shot. 

Why Choose a Rifle Scope

There are several reasons to choose a rifle scope over a low-power variable optic (LPVO) or reflector/holographic sight. One is power. LPVO sights can magnify an image, but you need magnification and light for long-distance shooting. A larger objective lens gathers more light, increasing the brightness and clarity of the image. 

A powerful rifle scope is suitable for long-range shooting in both competitive and hunting scenarios. In a tactical setting, it enables the military or law-enforcement sniper to extend the distance of his weapon far beyond what is practical with non-magnified optics or iron sights.

Magnification Range

One of the most distinct advantages of a rifle scope compared to other sighting systems is power. A rifle scope designation denotes magnification and objective lens diameter. For example, a 1–4×42mm scope would have a magnification range of 1 to 4 power and an objective lens diameter of 42mm. 

Most reflector and holographic sights are 1× and require a separate optical accessory for magnification. If you’re shooting targets at 100–200 meters, a magnification range of 1–4× is acceptable. This is appropriate for hunting, defending a ranch, farm, or homestead with a carbine, and many competitive applications (e.g., 3 Gun). 

For targets from 200–400 meters, a range of 5–8× should suffice. For ranges from 400–600 and beyond, 9–12×.

How a Rifle Scope Compares

Reflector and holographic sights use an LED or laser diode and a series of curved mirrors or collimating lenses to display a virtual image. These sights are typically non-magnified and allow for rapid target acquisition, especially at relatively close range. 

Many holographic sights use a dual-MOA reticle consisting of a 1-MOA dot enclosed in a 68-MOA ring, which can be useful for close-quarters battle

These types of sights enable you to engage close-range targets quickly in broad daylight and low-light environments. 

Low-power variable optics (LPVO) are versatile because they enable you to engage targets at both close and medium range. An LPVO has a magnification starting at 1× — this is an essential criterion. This has two advantages:

Reduced weight and bulk

The less powerful the scope, the lighter and more compact it can be, reducing the footprint on your rifle. For tactical rifles and carbines, a lightweight, short scope will disrupt the center of gravity less and render the weapon more comfortable to transport. 

Increased situational awareness

Low and zero magnification can allow you to keep both eyes open, increasing your peripheral vision and situational awareness. For tactical or hunting scenarios, this can be a lifesaver.

Eye Relief

Eye relief is the distance between the rear sight or eyepiece and your dominant eye. If you place the scope too far forward, the target image may appear out of focus or surrounded by a black ring. Too close, and you may experience what’s called “scope bite” — where the eyepiece strikes your eye under recoil. 

Correct eye relief should provide you with a full field of view and a sufficient buffer for safe shooting. However, eye relief is affected by more than the scope. You should always strive to achieve a consistent stock weld — your cheek’s position on the rifle stock’s comb. 

Reflector sights provide substantial eye relief — some manufacturers list this as infinite. It’s why you see these types of sights on handguns. With a traditional rifle scope, the eye relief is determined by several factors.

Standard eye relief

Standard eye relief for a centerfire rifle scope is 3.5 to 4”. If you’re shooting at an incline — i.e., upward — you should opt for a rifle scope with longer eye relief. However, recoil also affects the distance.

Long eye relief

If you’re firing a rifle chambered in a more powerful cartridge, a longer eye relief of 4.5” or more will improve your safety. This type reduces the amount of magnification available to you and is more appropriate for shorter ranges. 

For close-range engagements, whether 3-Gun matches or armed assailants, an LPOV or reflector/holographic sight is more useful.

Parallax

Optics manufacturers often advertise reflector sights as being parallax free. This is an exaggeration, but the parallax that does exist is minimal. Your accuracy when using a rifle scope can be significantly affected by this phenomenon. High-quality rifle scopes feature parallax adjustment in the form of a rotating ring or turret.


Additional Features 

Several features can increase the long-term durability, usability, or accuracy of your rifle scope. 

One-piece construction

For increased durability, the manufacturer should machine the scope tube from a single piece of material — usually an aluminum alloy, such as 6061 T6.

Lens multi-coatings

Rifle scope makers from Leupold to Schmidt & Bender apply multiple lens coatings. These coatings serve several purposes. Some protect the lenses from surface abrasion. Others reduce glare and maximize light transmission to increase the clarity of the target image. 

Gas purging

To reduce fogging, a rifle scope tube should be purged at the factory with a gas. The industry standard is nitrogen; however, argon is a popular choice among some manufacturers. 

Throw lever

For rapid adjustments to magnification, you can choose a scope that features a throw lever. This is a bar attached to the power ring that allows you to switch from low to high magnification in a variable-power scope by simply rotating it from left to right. 

Shock resistance

Accidents happen, and ideally, dropping your rifle won’t break your optic. However, shock resistance also determines how well your scope can withstand recoil. You should always ensure that the scope you buy is rated for the cartridge you want to fire.


​Training is Essential

If you want to see your target clearly at long ranges, a rifle scope is an excellent accessory. However, a rifle scope is only part of the marksmanship equation. You need to practice the fundamentals of marksmanship extensively and familiarize yourself with how your equipment works to achieve the best results. 

Do you know positions, trigger control, breath control, and sight picture? Do you know how to sight in your rifle, how to account for wind, barometric pressure, humidity, and other factors that affect the bullet in flight? All these skills will define you as a marksman.  


Final Word

A rifle scope offers precision and greater magnification compared with other types of sights for long-range shooting. However, if you don’t need to hit targets far away, you may be better served by a close-range optic or iron sights.

You can also check out:

Red Dot Optics: An Introduction

Best Air Rifle Scopes in the Market

Best AR-15 Scopes Under 300

Best Cheap Rifle Scopes

Best Thermal Scope for Coyote Hunting

Advantages of a Rifle Scope

To learn more about adjusting rifle scope, you may check out this guide.