Scopes Optics, Tactical Reviews

How does a red dot sight work?

vortex red dot sights multiple types
Examples of different kinds of Vortex Red Dot Sights
Red dot sights are popular on pistols, shotguns, rifles, and even airsoft guns, for a variety of reasons. They allow for fast target acquisition, allow for both-eyes-open shooting, and are generally more rugged and reliable than iron sights. But how do they work?
If you have not yet bought your red dot sight, you can view a bunch of comparisons and guides here on our site..
If you are looking for a red dot sight for your Glock 17 or Glock 19, check this out.

How Red Dot Sights Work

Introduction to red dot sights and their purpose.

Red dot sights are a type of optical sight that are commonly used on firearms such as rifles and shotguns. They are designed to help the user quickly and accurately aim at a target by providing a red dot or other reticle that the user can align with the target.
Red dot sights work by using a collimator, which is a device that projects a beam of light onto a transparent lens or glass window. The light is focused onto a single point, creating a red dot or other reticle that the user can see.
The user looks through the lens or window and aligns the red dot with the target using adjustable windage and elevation controls. This makes red dot sights easy to use and intuitive, even for inexperienced shooters.
Red dot sights are popular among hunters, target shooters, and military and law enforcement personnel because they can improve accuracy and speed up target acquisition. They are also widely used in sports such as 3-gun competitions and tactical shooting.

Description of the basic components of a red dot sight

The basic components of a red dot sight include the LED or laser emitter, the reflector, and the reticle.
The LED or laser emitter is the source of the red dot or other reticle that the user sees. The emitter uses a small light-emitting diode (LED) or laser to project a beam of light onto the reflector.
The reflector is a curved mirror or lens that is mounted inside the red dot sight. It is positioned in front of the LED or laser emitter and reflects the beam of light onto the reticle.
The reticle is the red dot or other aiming point that the user sees when looking through the red dot sight. It is typically a small, bright dot or crosshair that is superimposed onto the user’s field of view. The reticle is mounted on the same plane as the target, so when the user aligns the dot or crosshair with the target, the bullet will hit the target.
Some red dot sights also have additional components, such as windage and elevation adjustments for fine-tuning the dot or crosshair’s position, and brightness controls for adjusting the intensity of the reticle. Some red dot sights also have multiple reticle patterns or colors, allowing the user to choose the one that best suits their needs.

Explanation of how the LED or laser emitter projects onto the reflector

When the red dot sight is turned on, the LED or laser emitter projects a beam of light onto the reflector. The reflector is a curved mirror or lens that is mounted inside the red dot sight, and it is positioned in front of the LED or laser emitter.
The reflector reflects the beam of light onto the reticle, which is the red dot or other aiming point that the user sees when looking through the red dot sight. The reticle is mounted on the same plane as the target, so when the user aligns the dot or crosshair with the target, the bullet will hit the target.
The LED or laser emitter, reflector, and reticle are all carefully aligned and calibrated to ensure that the red dot or other reticle is accurately positioned relative to the target. This allows the user to quickly and easily align the red dot with the target, improving accuracy and speed.
This is an interesting video that was very insightful for learning about Red Dot Sight Physics:

How does a shooter look through the red dot sight?

To use a red dot sight, the shooter first mounts the sight onto the firearm, typically on the top of the barrel or receiver. The shooter then looks through the lens or window of the red dot sight and positions the firearm so that the reticle is aligned with the target.
The shooter can adjust the position of the reticle using the windage and elevation adjustments on the red dot sight. These controls allow the shooter to fine-tune the position of the reticle so that it is accurately aligned with the target.
Once the shooter has aligned the reticle with the target, they simply place the red dot or other aiming point on the target and pull the trigger. This allows the shooter to quickly and accurately aim at the target, improving their chances of hitting the target.

What are the advantages of using a red dot sight?

One of the main advantages of using a red dot sight is improved accuracy. Because the red dot or other reticle is superimposed onto the shooter’s field of view, the shooter can easily and intuitively align the dot with the target. This allows the shooter to shoot more accurately and consistently, improving their chances of hitting the target.
Another advantage of using a red dot sight is faster target acquisition. Because the shooter can quickly and easily align the red dot with the target, they can acquire and engage targets more quickly than with traditional iron sights or other types of optical sights. This can be especially beneficial in situations where the shooter needs to quickly engage multiple targets or moving targets.
Red dot sights are also relatively simple and intuitive to use, making them a good choice for inexperienced shooters. They are also lightweight and compact, making them easy to mount on a variety of firearms.
The use of a red dot sight can greatly improve a shooter’s accuracy and speed, making it a valuable tool for hunting, target shooting, and other shooting sports.

Wrapping up How Red Dot Sights Work

Red dot sights are a type of optical sight that are designed to help the user quickly and accurately aim at a target. They work by projecting a red dot or other reticle onto a transparent lens or glass window that the user looks through. The user aligns the dot with the target using windage and elevation controls, and then simply places the dot on the target and pulls the trigger.
The use of a red dot sight can greatly improve a shooter’s accuracy and speed, making it a valuable tool for hunting, target shooting, and other shooting sports. Red dot sights are also relatively simple and intuitive to use, making them a good choice for inexperienced shooters.

The Red Dot Sight Reticle

Red dot sight reticles are typically measured in minutes of angle (MOA), which is a unit of angular measurement. One MOA is equal to one sixtieth of a degree, or approximately one inch at 100 yards.
The size of the red dot or other reticle is expressed in MOA. For example, a red dot sight with a 3 MOA reticle will have a dot or crosshair that is 3 inches in diameter at 100 yards. A larger reticle, such as a 6 MOA dot, will be twice as large at the same distance.
The size of the reticle is an important consideration because it affects the accuracy and speed of the red dot sight. A smaller reticle, such as a 3 MOA dot, will be more precise but may be harder to see or acquire quickly. A larger reticle, such as a 6 MOA dot, will be easier to see and acquire but may be less precise.
The most commonly used reticle sizes in red dot sights are 3 MOA and 6 MOA. Some red dot sights also have reticles with other sizes, such as 2 MOA or 8 MOA. These sizes are less common but may be suitable for certain applications or personal preferences.
The size of the red dot sight reticle is a matter of personal preference and depends on the intended use of the red dot sight. Some shooters prefer a small, precise reticle for long-range shooting, while others prefer a larger, more visible reticle for faster target acquisition.
If you are unsure about what MOA you should get, check out this guide we made comparing 3 MOA to 6 MOA.

What is a Red Dot Sight good for?

Red dot sights are good for many applications, including hunting, target shooting, and tactical shooting.

Red dot sights are popular among hunters because they can improve accuracy and speed up target acquisition. The use of a red dot sight allows the hunter to quickly and easily align the red dot with the target, making it easier to hit the target and reducing the chances of missing or wounding the animal.

Red dot sights are also popular among target shooters, both for casual shooting and competition. They can improve accuracy and speed up target acquisition, allowing the shooter to shoot more accurately and consistently.

Typically, a red dot sight can help you aim at a target up to 100 yards away without needing any magnification. Because there is no magnification, the shooter does not need to worry about parallax or eye relief. This is good for guns with heavy recoil that might kick a normal sight into the shooter’s eye.

Red dot sights are also widely used in tactical shooting, such as by military and law enforcement personnel. They are fast, accurate, and easy to use, making them a valuable tool for engaging targets in high-stress situations.

These sights can be mounted at various distances from the shooter’s eye without worrying about focus; sights can be placed in any mechanically-convenient mounting position, such as the carrying handle, or on a rail system (typically a Picatinny rail) on top of the rifle.

Red dot sights are a versatile and useful tool that can improve accuracy and speed up target acquisition in a variety of shooting applications.

Do red dot sights need to be sighted in?

Yes, red dot sights typically need to be sighted in before they can be used effectively.
Sighting in a red dot sight involves adjusting the windage and elevation controls on the red dot sight so that the reticle is accurately aligned with the target. This is typically done by shooting a series of test shots at a known distance and then making adjustments to the windage and elevation controls until the reticle is accurately aligned with the point of impact.
Once the red dot sight is sighted in, the user can align the reticle with the target and shoot with confidence, knowing that the bullet will hit the target where the reticle is placed.
Sighting in a red dot sight is an important step that should not be skipped, as it ensures that the red dot sight is accurate and effective. Some red dot sights come pre-sighted from the factory, but they may still need to be adjusted to account for changes in the firearm or the shooter’s technique.

How to Sight in a Red Dot Sight Without Shooting?

To sight in a red dot sight without shooting, you can use a bore sight, which is a device that allows you to align the red dot sight with the bore of the firearm.
To use a bore sight, you first need to remove the bolt or other action from the firearm and attach the bore sight to the bore. The bore sight typically has a laser or other aiming device that projects a dot or other reticle onto a target at a known distance.
Next, you need to look through the red dot sight and adjust the windage and elevation controls until the reticle is aligned with the dot or reticle from the bore sight. This will roughly align the red dot sight with the bore of the firearm, allowing you to shoot a few test shots at a known distance to fine-tune the alignment.
While bore sighting can be useful for getting a rough alignment of the red dot sight, it is not as accurate as actually shooting a few test shots. It is recommended to shoot a few test shots at a known distance to fine-tune the alignment of the red dot sight and ensure that it is accurately sighted in.

Quick and Dirty

If your iron sights are already zeroed / sighted to your liking, then simply adjust your red dot sight to align with the rear and front site.

To use a Bore Sight

This way uses a quality bore sight laser, such as the LaserLyte Universal Laser Bore Sight
  1. Ensure you have mounted the red dot sight to your weapon.
  2. Set the weapon on a stable firing platform, so you can make adjustments minimal disturbance to the weapon.
  3. Turn on the bore sight laser and aim it at the center of the target. This could simply be a paper target taped to your wall. However, we recommend sighting at the distance you generally plan to engage. Probably less that 100 meters.
  4. Peer through the red dot sight to see where the dot appears in relation to your larger on the target.
  5. Use any flat tipped tool to adjust windage (left-right directions) and elevation (up-down directions) in order to pull the red dot from the sight onto the red dot on the target.

Does a red dot sight require a battery?

Yes, most red dot sights require a battery to power the LED or laser emitter that projects the red dot or other reticle.
The type of battery used in a red dot sight depends on the specific model and design. Some red dot sights use small, coin-style batteries, while others use larger batteries such as AAA or CR123.
The battery life of a red dot sight varies depending on the model and the brightness settings of the reticle. Some red dot sights can last for several thousand hours of continuous use on a single battery, while others may need to have the battery replaced more frequently.
It is important to check the battery regularly and replace it as needed to ensure that the red dot sight is always ready for use. Some red dot sights have low-battery indicators that alert the user when the battery is running low, but it is still a good idea to check the battery regularly to avoid any unexpected failures.

The red dot is visible in the sight, and it does not require any other power source.

Check out the rest of our site for reviews of specific Red Dot Sights. Here is a small summary of sites with their respective battery life:

Who can use Red Dot Sights?

Red dot sights can be used by anyone who is legally allowed to possess and use a firearm.
Red dot sights are commonly used by hunters, target shooters, and military and law enforcement personnel. They are also widely used in shooting sports such as 3-gun competitions and tactical shooting.
Red dot sights are relatively simple and intuitive to use, making them a good choice for inexperienced shooters. However, like any other optical sight, they do require some practice and familiarity to use effectively.
Red dot sights can be used by anyone who is legally allowed to possess and use a firearm and who is willing to practice and become familiar with the sight.

Different types of red dot sights

There are several different types of red dot sights, including reflex sights, holographic sights, and prism sights.
Reflex sights are the most common type of red dot sight. They use a simple, straightforward design that projects a red dot or other reticle onto a transparent lens or window that the user looks through. Reflex sights are lightweight, compact, and easy to use, making them a popular choice among shooters.
Holographic sights are a newer type of red dot sight that uses a holographic reticle. The reticle is a three-dimensional image that is superimposed onto the shooter’s field of view, allowing for greater accuracy and precision. Holographic sights are more complex and expensive than reflex sights, but they offer some advantages for certain applications.
Prism sights are a type of red dot sight that uses a prism to project the reticle onto the shooter’s field of view. Prism sights are larger and heavier than reflex or holographic sights, but they offer a wider field of view and improved optical performance. They are commonly used on long-range rifles and other precision shooting applications.
The choice of red dot sight depends on the intended use and personal preferences of the shooter. Different types of red dot sights offer different features and benefits, and the best choice will depend on the specific needs and preferences of the shooter.