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Choosing the Best AR-15 Red Dot Sight for Your AR 15

For fast acquisition of targets and an easy use sighting system, you can’t beat a red dot sight.

These types of sights feature an illuminated “red dot” that functions as an accurate aim point for the operator. An AR-15 red dot sight is primarily meant for targets within 100 yards, but it can also work for longer ranges.

AT3 LEOS Red Dot Sight on Rail

How Does a Red Dot Sight Work?

For you to be able to choose the best red dot sight for your AR-15, it is important to learn first how red dot sights work.

The red dot sight is often known as a reflex sight, which is a term stemming from the fact that red dots rely on non-magnifying reflectors to display the red dot. Basically, a small LED generates a colored dot of light, which reflects against a small spherical mirror. The mirror focuses the dot on a lens, which is what you see when you look through the sight.

reflex sight diagram

On more advanced (and expensive) red dot sights, additional lenses may be added to the setup to eliminate “parallax”. What is parallax? It refers to changes in the position of the dot when you look at it from different angles.

For example – you put your gun in a vise with the red-dot sighted right on your target’s bulls-eye. When if you move your head to a different angle and look through the sight, is the dot still on the bulls-eye? Hopefully, the answer is yes – that means that your red dot is “parallax-free”. This enhances the overall accuracy and usability of the sight. But be prepared to pay a little extra for a truly parallax-free sight!

Different Types of AR-15 Red Dot Sights

Red Dot Sights come in many shapes and sizes. “Tube” style sights look a lot like a scope, while “open” style sights are more of a square shape (Eotech red dot sights are a good example of this).

The dot size, dot pattern, and dot color are some of the important considerations in choosing the right red-dot sight for your AR-15. You are the operator so your eyes, usage, the mission package and the configuration of your AR-15 would come into play in choosing your red dot sight.

red dot sights reticles

The dot size should be big enough for you to easily see, but not too large to obscure targets. Dot size is typically measured in MOA (“minutes of angle”). Essentially, 1 MOA means roughly 1″ at 100 yards. So if you have a 5 MOA dot, that means this dot covers a 5″ area on a target 100 yards away. For a general use AR-15 red dot sight, we recommend MOA between 1 and 4 MOA. Anything larger than 4 MOA will just get in the way.

The dot pattern (AKA the reticle) is largely personal preference. Most sights have a dot (hence the name red dot), but you can also get reticles shaped like crosshairs, or many other patterns. Some sights have adjustable reticles and allow you to quickly switch between different reticle styles.

The last main choice is the color of the dot.

Wait – it’s a red dot sight so the dot is going to be red, right?

Not necessarily – green and blue are also available. From our experience, red is the best all-around color, but blue can be easier to see in certain bright-light conditions. It’s best to try a couple of different sights and see what you prefer.



AR-15 Red Dot Sights vs Scopes

For a sight that works well on shorter-range shooting (less than 300 yards), the red dot sight can be a great choice. They typically weigh less than a scope and are much better for quick target acquisition. Also, there will be no “tube effect” that is typical with a scope (due to the varying eye relief on scopes). Basically, a red dot is much simpler to use but lacks the magnification of a scope.

If you want some magnification, one option is to get a flip-to-side magnifier that goes behind your red dot. This allows you to flip the magnifier to quickly magnify your red dot for long distance shots. Despite that added weight, this is a versatile option that is worth looking into. Some red dot sights are available in a kit that includes the magnifier, like the Magnified Red Dot Kit pictured below.

AT3™ Magnified Red Dot Kit

Perhaps the biggest downside of a red dot sight is that it requires batteries. No batteries, no dot! But on most red-dots, batteries last so long it’s not an issue. For example, on the RD-50 Red Dot Sight, the battery lasts up to 50,000 hours between replacements.

Best AR-15 Red Dot Sights

There are many choices available for red dots, and everyone seems to have an opinion on the best red dot sight for AR15.
But we have 3 categories of recommendations: Best Value, Best Overall, and Other Excellent Red Dot Sights.

Best Value Red Dot Sights for AR 15: AT3 Red Dot Sights

Looking for a great red dot sight on a budget? AT3 red dot sights are the place to start, with 2 popular models to choose from.

The AT3 RD-50 PRO Red Dot Sight

AT3 RD-50 PRO Red Dot Sight

At a price under $100, the AT3 RD-50 PRO Red Dot Sight is an unbeatable value. It’s tough, lightweight, accurate, and easy to use. The RD-50 PRO features a crisp 2 MOA dot, a lightweight riser with several height configurations, and an armored housing with integrated lens caps.

Other key features are a waterproof, shockproof design; crystal-clear multi-coated lenses; and up to 50,000 hr of battery life. Plus, all AT3 products are backed by a transferable Lifetime Warranty.

Included with the RD-50 PRO is the new PRO-MOUNT Riser – a premium lightweight riser mount that serves as the perfect companion for any AR-15. There are 2 mounts heights available – a medium .83″ riser for “absolute” cowitness with AR iron sights, and a 1″ high riser for lower 1/3 cowitness.

In addition, the RD-50 PRO includes RD-ARMOR – a cover with integrated lens caps that protects your red dot sight from scratches, dust, and moisture.

If you want a red dot sight that is lightweight, dependable, accurate – at a price that won’t break the bank, you can’t go wrong with the the AT3 RD-50 PRO.

The AT3 LEOS Red Dot Sight with Laser

AT3™ LEOS™ Red Dot Sight with Integrated Laser Sight & Riser

The AT3 LEOS Red Dot Sight is designed for the AR-15 rifle and is packed with features like red targeting laser, integrated riser mount, flip up lens caps, and tool-free windage & elevation adjustment. The both the laser and red dot are controlled with easy push-button controls.

Just like the RD-50-PRO, it features up to 50,000 hr battery life, and a durable, waterproof, and shock resistant design that unfailingly stays on target.

For an accurate, dependable AR-15 red dot sight that’s packed with features, the AT3 LEOS can’t be beaten.

Best Overall AR-15 Red Dot Sight: The Trijicon MRO Red Dot Sight

Best Red Dot Sight Overall - Trijicon MRO Red Dot Sight

(Note – all links for the MRO redirect to Amazon – we’ve found that they have the best pricing for this sight)

Launched in 2015, the MRO (Miniature Rifle Optic) is a relative newcomer to the red dot space. But we believe that the quality, functionality, durability, and decent price (under $500) of the MRO puts it ahead of the competition, and it’s our top overall red dot sight.

Trijicon is best known for their legendary ACOG rifle scopes, which have been the go-to military optic for mid-range applications for over 20 years.

The Trijicon MRO red dot sight packs many of the best features of the ACOG into a small red-dot sight. The forged aircraft-grade housing is as durable as you’ll find and even waterproof up to 100 ft. The glass quality is superb, with exceptional clarity and a crisp red dot reticle. The MRO offers 3 choices of mounts – low, medium, and high – with the medium and high mounts designed for co-witness on AR-15.


Other Excellent Red Dot Sights

EOTech Holographic Red Dot Sights

EOTech Holographic Red Dot Sights

EOTech is a premier manufacturer of Holographic Red Dot Sights that allow heads-up, 2-eyes-open shooting. EOTech red dot sights come in many different styles and reticles, some of which are made for specific calibers like .223, .308, and .300 Blackout.

What makes the EOTech sights so great? For one, they are reliable – these sights are used extensively in combat and law enforcement. They also have excellent low-parallax optics and unique rectangle-shaped lenses for a wide field of view. Many of the EOTech red dot sights are also night-vision compatible.

In 2015, EOtech’s parent company lost a fraud lawsuit, where they were implicated in knowingly selling defective sights to the US military and government agencies. The company recalled many red dot sights after this, and they say they have since addressed the issues, but this incident damaged EOtech’s reputation in the firearms community.

Now that these issues are addressed, we think that EOtech sights are still an excellent choice. Want to learn more about EOTech sights? Check out our selection guide and comparison chart.

Aimpoint Red Dot Sights

Aimpoint Red Dot Sights

Aimpoint is a Swedish optics company that makes red dot sights for civilian, police and military use. It is Aimpoint’s belief that a weapon sight should simplify aiming while performing reliably under the toughest conditions. And they most certainly succeed in that.

Aimpoint sights are regarded by many as the best sights on the market – and for good reason – they are nearly indestructible red dot sights with excellent battery life. Aimpoint sights are pricey, and the functionality is fairly basic, but you cannot go wrong with an Aimpoint.

Best AR-15 Red Dot Sight Comparison Chart

Product Price (MSRP) Max Battery Life Dot Size Weight
Trijicon MRO $579 50K Hours 2 MOA 4.1oz
Eotech 512 $459 1K Hours 1 MOA Dot & Ring 11.5oz
Aimpoint Micro T-2 $846 50K Hours 2 MOA 3oz
AT3 RD-50 PRO $99.99 50K Hours 2 MOA 4.7oz

This chart compares some of the most popular red dot sight models on the key attributes of price, battery life, dot size, and weight.

One Last Tip

If there’s anyone that knows the AR-15 platform, it’s the US military. As a special offer for our readers, you can get the Official US Army Manual for AR-15/M4/M16 right now – for free. Click here to snag a copy.

22 thoughts on “Choosing the Best AR-15 Red Dot Sight for Your AR 15

  1. Thanks, you make doing research easy. Can’t wait to receive my free U.S. Army manual for M4/M16/AR15.

  2. Love your articles on various AR gear/parts/pieces!

  3. Really it comes down to your check book and you own personal likes.

  4. Was at the range recently and asked a friend on the AZ DPS SWAT team about red dot sights and which one he had on his rifle. He said the AZ DPS SWAT team recently dumped the Aimpoint Pro Patrol and went to the Trijicon MRO because the Aimpoint simply wouldn’t hold up (both under $500). He had high praise for other higher priced Aimpoint products such as the COMPM4 (as do I, used one in Afghanistan) but everyone has a budget. No mention of EOtech one way or the other.

  5. Do you have any experience with or have heard about DI Optics RV 2?

  6. Have age related macular degeneration. It has been suggested that a red dot will let me shoot with both eyes open as one eye is still ok. Your thoughts

  7. I’ve owned an eotech exps2-0 sight for 3 years and I’ve never had the slightest problem, and I don’t exactly treat my guns and gear gingerly. I don’t live in a place where it gets down to -40 degrees Fahrenheit, so iv never seen the problem that they were recalled for. Just my two cents.

  8. How hard is it to dial in

  9. Currently running a Holosun (HS403GL) on a DDm4 V7 and so far it seems to be a great little optic for right at $200.

  10. Great article!

  11. Sir,
    I purchased your product for my AR Platform a while back and am extremely satisfied.
    I am currently on a wait list for a Ruger PC 9 . It will be strictly a pack gun that I have at the ready for situations when I travel . Probably ride under my pickup seat most of the time. A get home gun if you will. Can you give me an idea of which AT3 products you would recommend on a $500 rifle. Please and Thank You , Bobby

    1. I have the Ruger PC9 rifle with the AT3 LEOS with the red lazer and a AT3 flip to the side magnifier. Both optics work great and have been very reliable. (For me, just the LEOS was difficult to see the target much past 75 yards.) With the magnifier I can see out to 200 yards.

  12. Thank you for reaching out to us, Bobby! I highly recommend our RD-50. It’s our best seller for a lot of good reasons. It’s low cost but high quality, with a lifetime warranty to back it up.
    Ruger PC 9 seems to be getting more popular these days. Since it has an atypical sight profile, you will have to use the Yankee Hill Machine YHM-230 .3″ riser with the RD-50. Doing so will give you an absolute cowitness. We do not have this riser listed in our website but we have them in stock, in order to accommodate customers like you.

    Let me know if you are interested in this riser and I can email you a personalized quotation for it.

  13. Love what I hear about your co…
    Purchased on Amazon can’t wait to get
    It on my mini 14…
    I do have an Astigmatism hope it works
    Mild but… fingers crossed????

  14. Hello, Robert! The mini-14 is a little different. The front sight post is a little shorter than a standard AR-15 sight, so the RD-50 with no riser should yield an absolute cowitness.
    As for your astigmatism, let us know how the red dot works for you. If you encounter any problems, just reach out to us and we’ll try our best to assist you.

  15. […] Choosing a red dot sight can be a relatively easy decision if you make your choice based on price alone. But even if you choose something in the lower-price range or mid-price range, you should make sure your getting the right tool for your firearm and for the type of shooting you’re going to do. Base your decision on other factors, such as red-dot size, adjustable size, type of firearm and the mounting room you’ll need, whether your unit also has crosshairs. […]

  16. Would your company recommend the RD or the LEOS for an AR-15 red dot? I understand both will fit, Just wanted to get your opinion before buying one.

  17. Giving serious thought to your RD50 for the .300 AAC pistol I’m completing. Read good reports and talked with an owner that’s pleased. Probably have to wait until June as the last batch of parts almost emptied what I’d saved up for the project. But you will be hearing from me no later than mid June.

  18. AT3… You have renewed my faith in simplicity! In this age of ever increasing knowledge and information, it’s easy to get hyper-saturated and more confused than when you started. Your side by side comparison of optics choices for my AR15 was direct, easy to understand and by the end I was not only confident in my understanding but just as confident in your product! Bravo!

    1. Just bought the new Ruger 9mm Carbine, Model 19122. What height riser would you recommend? Not sure whether to get the RD-50 or RD-50 Pro. Currently have the RD-50 w/low mount on my Ruger Mini 14.

      Thanks for your help.

      Stephen Stuckert

  19. I bought an overlord mogadishu mile red dot , my ar15 has picatinny rails , I have Magpul mbs gen 2 flip sights , will it absulte co-witness , I’ve read 1/3 co-witness is preferred , your thoughts thank you

  20. I have a carry handle on my AR . Can I mount your red dot, with riser, on top of the carry handle and it work as effectively as if mounted on the rail w/o carry handle?

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