One of the most popular attachments for firearms today is the red dot sight.
You may have seen them on all kinds of guns; pistols, rifles, shotguns, and even other weapons, such as crossbows.
Discover what a red dot sight is, how it works, and what kinds of applications it is best suited for.
What is a Red Dot Sight?
Red dot sights are a type of non-magnified gunsight employing reflected light on a lens to project a highly visible point of aim for the shooter in the form of a red dot.
A typical red dot sight uses a battery-powered red LED and a collimating mirror to project the red dot back to the shooter’s eye.
Red dot sights are typically the firearm’s primary sighting system, replacing or supplementing iron sights. When iron sights and a red dot are used in conjunction, the practice is called co-witnessing.
In rarer cases, the red dot sight serves as a secondary sight, mounted on top of a primary, typically more powerful scope.
Avoiding confusion
The term “red dot sight” is generic; many red dot sight models do not project a red-colored dot – or even a dot-shaped point of aim. The red dot sight must also not be confused with a laser sight. Laser sights are externally-mounted devices projecting a laser beam, causing a visible red dot to appear physically on the target.
See Related Article: Mounting Your Red Dot Sight to Your Pistol
Similar sights
Specific red dot sight models may employ other light emission, and reflection systems than the standard LED and mirror, resulting in different names and designations.
For example, most EOTech products are holographic sights, employing lasers and a complex array of small mirrors to project a hologram, causing it to appear as though it is between your eye and your target.
However, and for all intents and purposes, holographic sights and other adjacent sight types (collimator sights, reflex sights, etc.) use the same basic principles and the same basic manual of use as regular red dot sights.
Purposes and Applications
At this point, you may be asking yourself: “What is a red dot sight good for?”
The primary purpose of a red dot sight is not necessarily shooting more accurately; instead, it helps the shooter aim more quickly. The lack of magnification means that a red dot sight is intended mainly for close to medium ranges.
A properly calibrated red dot sight allows the shooter to aim at the target faster and more efficiently than iron sights, eliminating the need to align the front and rear sights.
Like all optical sights, the shooter must zero their red dot sight at the distances they intend to shoot at before use.
Typical zeroing distances:
- 15 to 25 yards for handguns
- 50 to 100 yards for shotguns (may vary depending on ammunition)
- 100 yards for rifles
- On AR-15s, the battlesight zero technique is the most popular. An AR-15 sight zeroed at 50 yards is also roughly zeroed for 200 yards.
In theory, all the shooter needs to do is place the red dot on the target and press the trigger, sending a projectile into the point of aim, just like the crosshairs on a typical scope.
Typical applications
Red dot sights are compatible with any firearm possessing the appropriate mounting interface (e.g., Picatinny rails), from small handguns to large hunting rifles. They are useful in a wide array of situations:
- Plinking and general target shooting: The red dot sight is intuitive and easy to use, making plinking and target shooting more fun and more accessible.
- Competition: Red dot sights allow for faster target acquisition, making them a natural choice for competition guns. A skilled shooter can use a red dot sight on every type of competition firearm (pistols, shotguns, rifles, carbines). Most “race guns” intended for close-quarters shooting use a red dot sight of some sort.
- Home defense: Red dot sights are battery-powered. They do not require ambient light to function and can be used even in total darkness. When used in conjunction with a light, a firearm with a red dot sight makes for an excellent home defense platform.
- Military and law enforcement: Military forces and law enforcement units frequently use high-quality red dot sights on service rifles and carbines due to their durability, simplicity of use, and ability to withstand rough use and harsh conditions.
Advantages and Disadvantages
Now that you have the answer to “What is a red dot sight good for?” it is essential to understand the advantages and drawbacks of red dot sights.
As with everything when configuring a firearm, every choice introduces a compromise, and red dot sights are no different.
Advantages of using red dot sights
- Red dot sights are typically the shortest and lightest sighting system you can install on a firearm. Pistol red dot sights may weigh as little as 2 oz., making them very lightweight and convenient.
- They are intuitive and easy to use, even by the least experienced shooters. The red dot attracts and naturally focuses the shooter’s eye on the target.
- Unlike iron sights, red dots are more tolerant of imperfect alignment. Even if you shift your head, as long as the sight is on the target, the red dot will remain on target.
- Most long gun red dot sights fit on standard Picatinny rails, making them easy to install and remove from your firearms.
- Older and visually-impaired shooters generally have fewer issues focusing on the red dot compared to traditional iron sights.
Disadvantages of using red dot sights
- Red dot sights are battery-powered. While the highest-quality models have a very long battery life or convenience features such as auto-on and auto-shutdown, batteries eventually run out, requiring the shooter to carry spares or use back-up iron sights to continue aiming.
- Quality red dot sights are generally relatively expensive. Inexpensive red dot sights are unreliable and may break, lose zero, or become otherwise unusable within months.
- Not all red dot sights come with the mount allowing them to interface with your Picatinny rail, and most handgun red dot sights require a specific mounting plate.
- The lack of magnification and the aiming point’s relative size means that red dot sights are difficult to use at extended distances. The further the target, the more likely the dot will obscure it, making precise shots challenging at best.
Should I Buy a Red Dot Sight?
Every kind of shooter can benefit from red dot sights. It’s rarely a bad investment to make, as long as you understand their inherent limitations and prioritize buying a quality product from a reputable manufacturer.
Although some may argue that beginners should learn the basics with iron sights only, red dot sights are very beginner-friendly and can help new shooters get into a new hobby more efficiently.
Curious about how these things work? Check our article on LPVO scopes to learn more.
Want to explore more rifle optics? Check our in-depth guide on prism scopes.
And while you're at it, you can also check out our:
Best AR 15 Scopes for the Money
How to Use a Laser Boresighter on Pistols (Read Article)