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How Does a Red Dot Sight Work? [Full Guide for Beginners]

How Does a Red Dot Sight Work

At this point, you may be considering getting a RED DOT SIGHT for your firearm.

(Or you already have one but don’t really know how to use it.)

With a red dot sight equipped on your gun, you can shoot with better precision and accuracy.

So, how do red dot sights work and why are they so well sought after?

We’ll be discussing how a red dot sight works, its pros and cons, its features, and why you might personally want them.

What Is a Red Dot Optic?

A red dot sight is a gun accessory you can attach to your gun of choice to help you aim better.

It does that by placing a red dot on the target through the scope you’re looking at.

Red dot sights shouldn’t be mistaken with LASER SIGHTS.

Laser sights work by beaming a laser directly on the target.

How Does a Red Dot Sight Work?

The technology behind red dot sights isn’t really complex.

Red dot sights work by relying on two integral parts: The Light Emitting Diode (LED) and the two curved lenses, which will reflect the light to pass through the reticle.

The special glass is specially coated so that only light from the LED can pass through.

The glass will project the image onto the FOCAL PLANE to infinity and add the red dot to show you where your bullet may land once you shoot.

Red dot sights can work in a different way too, but we’ll talk about that later.

Types of Red Dot Sights

There are other red dot optics that you can avail yourself of on the market.

They have different features that may affect how you shoot, so we’ll go through how they were built and how they function.

1. Reflex Sights

This is the more STANDARD and INEXPENSIVE type of red dot sight available since the inner mechanism of it is quite simple.

We already explained how reflex sights work, but we’ll provide more detail this time.

Reflex sight dots use energy-efficient LEDs to light up a dot onto the concave lenses.

There are two lenses in the tube that are concaved so that the light from the LED can be projected to the shooter as a floating image on the front lens.

Of course, the lenses are coated in something like COPPER so that only the LED will pass through the lenses.

No shooter wants to get confused by another light shining through the optics.

If you decide to use a MAGNIFIER with your red dot sight, you may notice that the light emitted from the LED will also be magnified. This may cause problems with your sight when shooting.

Usually, reflex red dot sights are sold CHEAPER than holographic sights since they come in tubes or as open lenses that are simply protected by a metal hood.

2. Holographic Sights

Holographic sights may appear similar to reflex sight dots, but they are actually made different.

Instead of containing two lenses to reflect the red dot, holographic sights use a laser that is bounced off a bunch of mirrors inside the tube.

Because of that, the parallax distortion in a holographic sight isn’t as bad compared to reflector sight dots.

Unlike the reflex red dot scope, if you use MAGNIFIERS with holographic sights, they will remain their original size.

The only DOWNSIDE to holographic sights is that they are way MORE EXPENSIVE than the former.

Features of Red Dot Sights

Red dot sights have several features that make these optical devices worth using:

#1 Illuminated Reticle

Red dot sights make use of an LED light or laser to create an ILLUMINATED RETICLE.

These reticles’ brightness can be adjusted, so the light can better fit your environment and ambient lighting conditions.

However, while BRIGHTER ILLUMINATED RETICLES are easier for your eyes to pick up, they may appear larger over your target and cause you problems when you shoot.

#2 Compact Size

Most red dot sights are quite COMPACT.

Whether you get a reflex or holographic sight, they are small enough that you won’t have to worry about them weighing you down in any way.

Even if you opt to get CLOSED SIGHTS, which are bulkier than open sights that only consist of a flat base and a single loop of material to support the glass, they are still easy to bring anywhere with you.

#3 Battery Life

If you think that you may have to suffer from your red dot sight dying on you in the middle of a hunt, you’ll be glad to know that the battery life of the LEDs is very efficient in conserving power.

You can expect tens of hundreds of hours out from your batteries before they die out.

You could always turn off your red dot sight when they’re not in use, but a lot of users don’t turn them off so that they’re always prepared. You may want to adjust its brightness setting as an alternative.

There are also several models that come with a SMALL SOLAR PANEL so you can extend your red dot sight’s life up to 50,000 hours longer.

#4 Adjustability

You can adjust red dot sights according to your location’s windage and elevation like any other optic sight accessory.

It’s important for any shooter to establish a PROPER ZERO for your weapons, so you should learn to do it properly.

Most shooters tend to use the Kentucky windage instead of readjusting their reticle.

Pros and Cons of Red Dots

Like any other gun accessory, there are advantages and disadvantages to using a red dot sight when you go hunting.

We’ll be listing them here so you know what you’re in for.

Pros of Red Dot Sights

  • You’re going to get faster target acquisition and more potential for accuracy.
  • You’ll be aligned to the target quicker than when you don’t have a red dot sight.
  • You can hit targets from longer distances since you have a guide to help you aim.
  • You also get to enjoy its LONG EYE RELIEF if you’re using firearms that have heavy recoil. If you use a short eye relief telescopic sight with it, it may hit your shooter’s eye.
  • Whether you get open sights or closed sights, these optics are still incredibly portable; you won’t have to worry much about finding space for it when you go out to shoot a few rounds.
  • Its battery life is efficient as well.
  • They are the ECONOMICAL CHOICE with their affordable rates. (We have a guide on affordable red dots if you’re interested in some top budget options.)

Cons of Red Dot Sights

  • If you get used to how a red dot sight works, your own target acquisition skills may suffer a lot.
  • The size of the reticle may cause you issues when you aim. BIGGER RETICLE SIZES mean they obscure more of the sight picture, leading to shooting with less precision.
  • The illuminated point also grows bigger if your target is farther away from where you’re situated.
  • You should also be prepared to have EXTRA BATTERIES on you while you hunt, just in case your red dot sights die out on you. That’s also another reason why some hunters bring BACKUP IRON SIGHTS with them just in case their red dot sight’s batteries drain in the middle of their hunting session.

Why Would You Want a Red Dot Sight?

Well, why wouldn’t you want a red dot optic?

Red dot sights are easy to use and won’t even cost you a pinkie finger if you want to purchase one.

Quick target acquisition is easier to achieve since you won’t have to conduct sight alignment with your rear sight, front post, and your target.

All you have to do is put the red light at your aiming point and SHOOT.

You can even use red dot scopes with both of your eyes open and with an infinite amount of eye relief, allowing you to shoot with superior situational awareness and field of view.

If you’re already convinced, you can check out our buying guide of the Top AR-15 Red Dots.

How to Shoot With a Red Dot Sight Properly

Here is the aiming process to get the proper sight picture using a red dot scope.

  • Mount your red dot sight on your gun.
  • The lens of the system sets your mark to infinity.
  • Adjust the brightness level of your illuminated dot or other reticle until you can see it clearly.
  • The radiation of the light source becomes visible due to the light flow.
  • Aim your gun at the target and sight in the red dot.
  • Fire a few bullets and check if you hit the target. If not, adjust your sight and eye position, then repeat the previous steps.

You can practice shooting with a red dot sight at a SHOOTING RANGE. That way, you can practice shooting at a close range, to moderate distances, and far ranges.

Red Dot Sights vs. Iron Sights

At this point, we’ll assume that you know what a red dot sight is and how it works.

On the other hand, IRON SIGHTS doesn’t use any type of optic.

It’s composed of two parts: The first part is mounted at the front sight of the firearm, and the other at the rear.

The shooter uses this by aligning the front and rear of the iron sights and uses that as a GUIDE to hit the target.

So while an iron sight has the SAME PURPOSE as a reflex sight, the way they work is totally different.

Frequently Asked Questions About Red Dots

If you still have some unanswered questions about how red dot sights work, here are some common questions about them:

What’s Better? Red or Green Dot Sights?

That depends on you.

Red dots are far more popular than their green counterpart, but for a good reason.

The human eye can sight in red objects easier than green objects due to their positions in the VISIBLE LIGHT SPECTRUM.

Red is the most prominent out of all the colors, while green falls somewhere in the middle.

But while your eye movement may detect red better than green, the color red also causes more STRAIN to the human eye.

Do Red Dots Work at Night?

Red dots work at night and with any kind of light source.

You can also get NIGHT VISION RED DOT SIGHTS that are meant to be used in low-light conditions.

Not only that, they work better when your point of aim directs it in a DARK BACKGROUND.

Are Red Dot Sights Accurate?

Getting your point of aim to be more accurate with an illuminated dot will also depend on your own skill when handling a gun.

You can’t expect to pick up an optical device and get better results immediately — you have to TRAIN with it to get better!

If you mount your red dot correctly and get it to zero for the distances you need, then you may find yourself hitting your targets with better accuracy without taking up too much time.

You should also remember that a smaller dot is better than a larger dot since you’ll be able to see more out of the front glass sight picture.

Red Dot Sights vs. Reflex Sights

As we mentioned in this article, REFLEX RED DOT SIGHTS (reflector sights) are actually a type of red dot sight.

These red dot sights work by using specially coated concave glasses that will only allow light from the light source to come through.

That way, only the light that the LED projects will pass through and land on one plane of the reflector sight.

With that, you’re able to view a red dot that will guide you when you need to take a shot at your target.

So while all reflex optics are red dot sights, not all red dot sights are reflex scopes.

What Is MOA?

MOA stands for Minutes of Angle.

This has something to do with the size of your light beam and how much it will cover certain distances.

So 1 MOA is equal to 1 inch at a 100-yard distance.

A red dot of 2 MOA will be SMALLER than a red dot of 6 MOA.

Final Thoughts

Now that you know how a red dot sight works, you should be able to decide whether you want them or not.

They’re great to use in close quarters, and they offer a lot of stealth if you ever need it.

There are a hundred different kinds of these optics from the original design — from Shield sights and newer ones you can also get from Aimpoint.

Just remember that while red dots are useful, that doesn’t mean you should only rely on them ALONE.

Your skills as a shooter will also shine through while you use them, so keep practicing your accuracy and precision.

We hope this beginner guide gave you all the information you need to pull the trigger on getting a brand new red dot sight!

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