Red dot sight with a magnifier or magnifying optics is a popular accessory device which purpose is to assist your aiming by visually enlarging a portion of the image in the sight. Conveniently, such magnifier sights are made flip-to-side, so you can get the best performance both at mid- and long ranges.
Magnifiers can be used with almost any type of sights. Iron sights with a magnifier are not rare on the market, as well as holosights and red dot sights equipped with ones.
Types of magnifier optics
Generally, magnifying optics can be divided to several categories:
Flip-to-side magnifier vs. scope
Magnifying optics designed for quick in-battle use is often made flip-to-side. Such magnifiers offer some fixed zoom level (typically, 3x) or several fixed zoom levels (from 2x to 9x) without the ability to gradually adjust zoom. Flip-to-side magnifier optic is designed for situations where instant switch between close range fight and long range aimed shooting is required.
A telescopic optical sight or simply a scope is a more advanced optical system with better objective lenses that offers better light transmission and hence displays a lighter image in the reticle. A scope is commonly mounted on a rifle. Also, scopes allow precise zooming, deliver larger amount of magnification, and often provide various advanced adjustments such as diopter adjustment, elevation or windage control.
Fixed zoom vs. variable zoom
Magnifying scopes come in two varieties: with fixed and variable zoom. Typical value of the fixed zoom is 3x which offers a nice balance between magnification factor and the field of view. On the other hand, fixed zoom is not always practical if targets can appear at various ranges.
Variable zoom magnifiers allow you to switch between zoom levels. For instance, a 3-9x40 scope offers zooming between 3x and 9x, where the number 40 is the objective lens diameter.
There are a number of things to consider when choosing a magnifier to purchase. The most important of them are:
- Zoom factor. The scope providing 3x magnification makes the image look like it is 3 times closer to you. Depending on the effective range and typical scenarios you will be using the sight in you may want to stop on certain zoom level. Bigger is not always better here. Also, because of the limited field of view.
- Field of view. The field of view is what you see in the magnifier optics when aiming. The larger the zoom factor, the smaller is the field of view. And FOV is extremely important if you want to shoot moving targets, for instance when hunting. The small field of view means you cannot see the entire scene and thus cannot reliably predict further movements of the target. You should find a balance between the field of view and magnification, and that depends on specifics of your duty and goals.
- Objective lens diameter. Bigger lens means more light and easier aiming. On the other side, bigger optics always brings in additional weight.
- Eye relief. Put this as simple as possible, eye relief is a distance between your eye and the rear side of the scope. If you place your eye at this distance you will see a full, non-vignetted image in the magnifier optics. Too short eye relief distance of the scope coupled with a heavy recoil weapon can be dangerous due to possible eye injury!
- Exit pupil. Optical sights concentrate the gathered light into a narrow pupil on the rear end of the optical system. The size of this “hole” is objective diameter divided by the magnifier strength. For instance, a 40 mm 3x objective has an exit pupil of 13.3 mm. Ideally, the size of the exit pupil must match the size of the shooter’s iris in normal working conditions. Which means there is no “one size fits all” exit pupil parameter, its value depends on conditions you will use the magnifier in. For instance, if you intend to use a magnifying scope at night time when your pupils are larger, you need a scope with larger exit pupil for optimal light usage.
Can you use a magnifier with iron sights? Yes, of course! In fact, you can easily improve your aiming and become a better shooter for a very affordable price. Just mount a magnifier on your gun!