Advances in electronics and optics have helped shooters strengthen and refine their aim. In particular, red dot sights, also known as red dot optics, are among the most popular options in the market today. They are usually small, electronic sight systems that generate a dot-shaped reticle that serves as a designator for where your rounds should land.
The reason why they’re so popular is that they allow for fast target acquisition, as you can get sight picture far more quickly than you can when using a flash front sight picture. They’re also extremely accurate.
If you’re buying your first red dot sight or wondering what use you could make of it, this article may be very useful to you. Here you can learn the basics of red dot sights: what are the different types of red dot optics, how they work, what are the benefits of using one and how to choose the best device for your needs and shooting habits.
What Is a Red Dot Sight?
More than a specific type of sight, red dot sight is a general term used to describe any kind of weapon optic that uses a red dot as an aiming point. In place of red dots, some sights have green dots or similar electronic images – such as crosshairs – as an aiming point (they’re still called red dot sights). When the average person thinks of red dot sight they are commonly thinking of an exposed reflex sight, but reflex sights are just one type of red dot sight. Other than reflex sights, in fact, there are prism sights and holographic sights.
Reflex sights are the most common type of red dot sights. They use a small LED that projects a colored dot of light against a lens. The lens works like a mirror, reflecting the dot of light back towards your eyes and allowing you to see the red dot through the sight. On more advanced and expensive red dot sights, additional lenses may be added to eliminate parallax (for a detailed explanation of the term, see the dedicated paragraph below). Parallax-free red dot sights ensure your aiming point to stay on the target even if you move your head around: the shooter can look through the sight from different positions without affecting the point of aim, which will remain fixed on the target.
Most of the reflex sights don’t have the tube-shaped design, but a small clear window through which the user can see the aiming point. However, those that have a tube-shaped design use a two-lenses system: the aiming point is projected forward from the rear lens to the forward one. The beam of the light would be contained within the tube.
Reflex sights have many advantages:
- They’re often cheaper than prism sights;
- They have unlimited eye relief, which means that your head can be positioned anywhere and you can keep both your eyes opened while aiming;
- They are also available for battery-free use.
On the other hand, the downfall of reflex red dot sights is that they aren’t magnified, but you could always integrate them with an RDS magnifier.
Reflex sights are an excellent option for many different weapons uses, such as home defense, tactical uses, and any type of general shooting. They’re recommended for the average rifle user.
Prism sights are usually short, tube-shaped optics. They work similarly to traditional lens scopes, but instead of a lens (or lenses), prism sights use a prism to focus the image you see down the scope. This feature allows prism sights to be much smaller than other types of traditional rifle scopes.
The biggest advantages that prism sights can offer are that (1) they’re commonly available with a small magnification, and (2) they allow for either etched or illuminated reticles.
Other than being more expensive than reflex sights, they also have another mayor downfall: their small eye relief. This means that your eye must be close to the optic to pick up a proper sight picture.
Prism sights are ideal for the average distance shooter (their magnification can improve accuracy at longer distances), but it wouldn’t suit those who need the fastest target acquisition (with prism sights is harder to reacquire the target because of the eye relief).
Holographic sights are less common than reflex or prism sights. This is mainly because only EOTEch has the patent for them, so EOTech holographic sights are the only in the market. They use a laser transmission hologram of a reticle image that is recorded in three-dimensional space onto holographic film at the time of manufacture. This image is part of the optical viewing window. The recorded hologram is illuminated by the light of a laser diode built into the sight. Due to such sophisticated technology, holographic sights are far more expensive than the other types of red dot sights. On the other hand, they’re top-quality optics, allowing the user to shoot with both eyes open, have a fast target acquisition and improving accuracy. EOTech sights are in fact recommended to anyone who needs extremely accurate shooting abilities such as competitive shooters – their only downfall, in fact, remains their price.
Why Do Shooters Need Red Dot Sights
Shooting isn’t merely pointing and pulling – technologies and new optics have taken it to the next level. With a red dot sight, you can be sure your shooting will live up to such standards.
They make a great advantage to beginners – those who are new to rifles can shoot using a red dot sight without the need for long training. They could use RDS in any shooting game or competition. Red dot sights can be a fantastic way to crush a beginner’s learning curve, but they can boost seasoned shooter’s accuracy and speed as well.
For hunters and skilled shooters, shooting the target only one shot can still be challenging. With a red dot sight, they can have proper guidance and visibility when they’re ready to pull the trigger. Red dot sights improve accuracy and the ability to lock the target fast so that hunters can have more chances of shooting the target with their first shot.
What Are the Benefits of Using Red Dot Sights?
Red dot sights have combined the advantages of iron sights and rifle scopes, but they also have features that no previous sighting system has offered. The two main benefits of using such devices are accuracy and speed – with a RDS you can pin your target more quickly and accurately than iron sights and even magnified optics.
Red dot sights allow the fastest target acquisition because of these features:
- The reticle is on the same focal plane as the target. This way, when the eye is focused on the target, it is also focused on the reticle. The shooter doesn’t need to shift their focus and face blurry sight while shooting at the target. This, combined with the possibility of shooting with both eyes open – is how aiming with red dot sights is quicker than with iron sights.
- Red dot sights have reduced parallax. Parallax is the tendency for a reticle to appear to move in relation to a target when the eye is moving behind the optic. Red dot sights are designed in a way that the position of the shooter’s head is not critical to accuracy, making the optic fast and accurate even in awkward positions.
- Red Dot Sights have no eye relief. Eye relief is the distance between your eye and the rear lens of a scope. When a device has a short eye relief your eye must be closer to the sight in order to see the entire image produced by the scope. With red dot sights, instead, you can mount your scope further up on the rifle so you can have a wider field of view and enhanced shooting accuracy.
- They project a very small dot (usually 1 MOA) that won’t obscure your field of view and ensure the highest level of shooting accuracy.
Understanding the Terms
Since this is a guide for beginners we thought of including an explanation for some terms complete beginners may not be familiar with.
Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight. When using a sight, the reticle can appear to move in relation to a target when the shooter moves their head (and eye) behind the optic. Red dot sights are parallax-free and this is a great advantage: it means that no matter how your head is positioned behind the optic and how you move it, the reticle will remain fixed on the target.
Minute of Angle (MOA)
A Minute of Angle is an angular measurement that is used to measure the illuminated red or green dot of a red dot sight. 1 MOA is equal to 1.047 inches at 100 yards (usually rounded down to 1 inch). This means that the red dot appears to be 1 inch in diameter on a target 100 yards out.
On one hand, the smaller the dot’s MOA, the harder to see. On the other hand, a larger dot would be a lot easier to see, but it may cover too much of the target at further distances and compromising shot accuracy. Red dot sights are usually used for short-range shooting – at such distances 1 MOA dots are ideal – they ensure accuracy and quick target acquisition: they would be visible without covering a broad area on your field of view.
The eye relief of an optical instrument is the distance from the last surface of an eyepiece within which the user’s eye can obtain the full viewing angle. When the viewer’s eye is outside this distance, a reduced field of view will be obtained.
Unlimited eye relief is one of the greatest advantages of red dot sights. They can be placed anywhere on your firearm that is most comfortable for you and your field of view won’t be compromised. Unlimited eye relief also ensures the quickest target acquisition, since you won’t have to pay attention to where your head is placed in relation to the eyepiece to have a full field of view.
Field of View (FOV)
Generally speaking, the field of view is the extent of the observable world that is seen at any given moment. In the case of optical devices, the field of view is the area the person can see through the device. When you’re using your RDS correctly you shouldn’t be worrying about the field of view: with both eyes open and target focus, you should barely be aware of the body of your RDS. You should look past the red dot sight and only see the red dot superimposed on your target. Because red dot sights usually lack magnification, the field of view with the RDS should be what we see with your own eyes.
Choosing a Red Dot Sight – What to Consider
There are a number of different types of red dot sights on the market with different prices and features. For anyone considering buying one, this section of the article is helpful to understand what are the main features to consider before making your choice.
Optical sight reticles are available in several forms. Common examples include dots, hollow circles, crosshairs, triangles and more. Any of them has its pros and cons: the best reticle type for you depends on your shooting needs and habits, but also on your eyes’ features (some may see dots better, other may simply refer other shapes because they have difficulty seeing a small dot, or they found it uncomfortable). This is how reticle shapes are usually used:
- Dots and open circles are the easiest to see and Center naturally.
- Circles, triangles, and harsh marks often correspond to specific target sizes and functions as range-finding tools.
- Crosshair allows you to quarter a target and help center your point of aim.
- Hash marks provide aiming points for targets beyond the shooter’s zero distance.
Red dot sights that provide adjustable brightness settings are more expensive but this feature is extremely important in several circumstances.
Adjustable brightness ensures you can see your dot with every light condition. When shooting to a close target, a sight set to its brightness position would make the reticle easier to acquire quickly. Instead, for larger distances reducing the illumination level would provide a finer aiming point.
Also, when shooting in bright daylight you want to be able to turn up your reticle brightness so that you can still be able to see the dot. On the contrary, when shooting at dawn or dusk – or with any circumstance where you have poor light condition – you want to turn the brightness down.
You can still make good use of a red dot sight that doesn’t feature adjustable reticle brightness, but – for the same price – always choose the device with adjustable brightness settings.
Red dot sights usually have no magnification. However, your device should still offer you a balance between easy and rapid sight acquisition and fine aiming point.
Reticles with small aiming points (1 or 2 MOA) are easier to aim precisely, even though it could a little more difficult to acquire your target quickly in a pinch. Most red dot sights feature a 1 MOA red dot, and if you’re a beginner you should opt for them.
Larger reticles can be harder to use, but skilled shooters can still make good use of them: they just vary their aiming technique so they can still use their sight with precision. For example: a 12 MOA triangle-shaped reticle – which is used in some Trijicon devices – may seem unsuitable for any target, but the reticle’s pointed tip can be used as a precise hold point.
With large circle reticle, once you’ve zeroed it at the appropriate distance, you can use the 12-o’clock portion of it to have accurate shots.
Red dot sights (non-magnified) that function without batteries are quite handy, but they have some limitations too. They usually feature fiber-optic equipped reticles that, in very bright condition, can wash out the target image. They are also extremely difficult to use in limited visibility situations.
If you opt for a sight that features a lithium battery, for the same price, always choose the device with the longer-lasting battery – it can be extremely useful when you need to adjust the brightness of your reticle, or when you use it at maximum brightness for a long time.
Red dot sightS usually have no magnification, but you can always integrate them with an RDS magnifier. If this is your intention, or you want to have this possibility in the future, check the magnifier compatibility of your red dot sight before purchasing it.
Night Vision Compatibility
If there’s a chance that you are going to use your red dot sight with a night vision device, always check the compatibility before purchasing your red dot sight. Only compatible RDS can be used with night vision devices; otherwise, your red dot sight can seriously damage your NVD’s optics and make it unusable.
Where to Mount Your Red Dot Sight
Since red dot sights have unlimited eye relief, you can mount your red dot sight anywhere along the top of your barrel. Some people prefer to have the RDS closer to the eye, others like it closer to the muzzle. The size of the dot as you see it will not be affected by where you mount it. Moving it a few inches forward or back won’t make it appear larger or smaller on your target.
Although you can mount your RDS anywhere on your weapon, some considerations must still be done:
- Don’t mount it on your handguard. It won’t be as consistent and slid and mounting it on the top of the receiver.
- If you’re going to use a magnifier along with your RDS, the magnifier should be mounted behind the sight.
- Your speed in picking up the dot can be a little faster when the optic is mounted closer to the eye.
- When shooting at distance, you can be a little more accurate when the optic is mounted further forward.
- When the sight is mounted closer to the eye, the field of view when looking through the optic will be wider but you’ll see less around it. On the contrary, when the sight is mounted further forward, the sight will block led of your view but you’ll have a small FOV when looking through it.
- The farther forward you mount your sight, the heavier your weapon will fell. It’s a question of balance and weight.
What to Mount Your Sight On
Since red dot sights are excellent for short-distance shooting, you want to mount yours on a weapon that would be used at shorter ranges, perhaps with multiple targets. (Using a red dot sight with, for example, long-range hunting rifles would make no sense).
The best choice is to pair your red dot sight with AR rifles. This is the most common use of red dit sights for both civilian home defense or quick target competitions and military and law enforcement usage.
There are also red dot sights designed to be paired with handguns. This is another good combination: you could quickly bring up your weapon, and just as quickly aim through your sight while maintaining observation of the area around the target.
Pros and Cons of Red Dot Sights
Red dot sights can bring a lot of advantages to your shooting, but they also have some limits. As we approach at the end of this article, let’s summarize them up.
- Red dot sights are perfect for beginners but also useful to more skilled shooters: in both cases, they enhance speed and shot accuracy.
- You have the option to go for a battery-operated red dot or a version that requires no battery at all.
- Unlimited eye relief.
- Reduced parallax.
- Reflex and holographic red dot sight allow you to shoot with both your eyes open
- There is no need of aligning the rear and the front sight when using red dot sights (as you should do with iron sights).
- Good quality red dot sights aren’t cheap.
- Usually, they don’t offer any magnification (in most cases, your best choice would be purchasing an RDS magnifier separately and spend more money).
- Unlimited eye relief is one of the best advance tea of RDS, but prism sights have a small eye relief, so it would be only suitable for users whose eye needs to be closer to the sight.
Are Red Dot Sights More Accurate
Other than increased speed, the greatest benefit of using a red dot sight is enhanced accuracy. Red dot sights make highly visible aiming points and allow the user to shoot with both their eyes open. They also have unlimited eye relief. To get the most out of your red dot sight you must use it correctly.
- Shoot with both your eyes open: when you keep both your eyes open you get the benefit of focusing both on the target and the reticle. This leads to faster target acquisition and improved accuracy.
- Red dot sights have reduced parallax, and in some cases, they are parallax free. Your head position behind the sight won’t affect your shot accuracy.
- An important factor that affects accuracy is the red dot size. Most red dot sights feature 1 or 2 MOA red dots which can provide the best accuracy. If you use a larger dot, you may need to change your aiming technique (we’ve already discussed how to make good use of larger dots).
Red dot sights are an extremely popular choice for competitions and sporting events as well as for military forces and services. Any shooter should consider purchasing one. With this article you learned anything you need to know to make a conscious choice among the dozens of types and brands of RDS on the market.You can choose between three types of sights (reflex, prism or holographic), and you are now able to consider each feature properly: eye relief, parallax, reticle size and shape, compatibility to other useful devices (such as magnifier or night vision devices) and more. We also tried to gave you good tips on where to mount your RDS, what weapon should be paired with it and how to get the most accurate shots out of it. Even if you are a complete beginner and purchasing your first ever red dot sight, we believe we’ve just given you the knowledge you need to make your purchase and start using your new device.