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Best Red Dot Magnifier Combos for AR-15s

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AR-15 rifles are among the most versatile rifle options available. Capable of being configured and customized to fit nearly any purpose for nearly any role, it’s no surprise that they’re one of the most popular platforms in America. Regardless of the configuration, one of the most popular optic choices for the AR-15 is a red dot sight.  

Red dot sights are a simple, yet highly effective optic solution for the AR-15. Their straightforward design, durability, and agility make them an ideal choice for a wide array of setups. Still, despite all their advantages, there’s one area where red dots fall short: range.  

Unlike other popular optics, like low power variable optics (LPVOs) and Prism Scopes, red dot sights don’t offer any magnification, making it a challenge to get a good sight picture on far away targets. While it isn’t impossible to hit targets past 100 yards with just a red dot, it isn’t always easy. Fortunately, this is where the magnifier comes into play.  

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Understanding Magnifiers 

What They Are and How They Work 

Magnifiers are a device that mounts behind a red dot sight, which provides additional zoom, extending its usable range. They increase the visibility of distant targets without distorting the reticle image, giving red dot sights a similar effectiveness as variable power optics.  

Essentially, in their simplest form, a magnifier is a type of prism scope, just without a reticle etched into it. They work by using glass prisms to physically shorten the optical pathways within the optic itself, folding the light in the process. In doing so, manufacturers can produce lightweight, low-profile optics with fixed magnification that can be used in tandem with reflex sights like red dot and holographic sights.  

Benefits of Using a Red Dot Magnifier 

Magnifiers offer a considerable number of advantages, the greatest of which being increased visibility. By enlarging the sight picture of the red dot sight, it becomes much easier to make consistent and accurate shots on targets at further distances.  

Additionally, in most cases, magnifiers come attached to cantilever mounts. This allows the magnifier to swing out away from the red dot sight, keeping it out of sight when not in use. When it’s needed, you can quickly shift it into position, allowing you to have a magnified red dot sight picture when needed. This is an incredibly valuable feature for those who need to be effective at range without compromising their close-quarters effectiveness. 

Compared to a variable power optic, such as an LPVO, a red dot and magnifier setup will offer certain benefits and drawbacks. We previously published a guide on the LPVOs vs. Red Dots and Magnifiers debate, which breaks down both options in a head-to-head comparison. 

Factors to Consider 

If you plan to run a magnifier with your red dot sight, there are some key factors to consider. One of the core considerations of a magnifier is the magnification level. There are a wide range of magnifiers available, with a few common magnification levels being 3x, 5x, and 6x. While each one can be used to great effect, depending on your barrel length, caliber, and intended use, you may benefit from one over the other.  

For instance, a 13- to 16-inch AR-15 chambered in 5.56 NATO has an effective range of around 500 yards. For these distances, a 3x magnifier is a solid option. If your rifle has a longer barrel or is chambered in a caliber that performs better at longer ranges, you’ll likely benefit more from a higher magnification level. Overall, the process is like choosing a prism scope’s magnification in that you want to find the one that best suits your needs.  

Red Dot Magnifier Options 

The number of magnifier options has increased significantly as they’ve become more popular amongst enthusiasts. The variety of available options can make it challenging to choose one, though. Below are some popular options to consider that will help round out your knowledge of what’s available:  

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Primary Arms Optics Magnifiers 

Our magnifiers are a high-quality yet economical option that pairs well with most reflex sights. As such, they’re among some of our best-selling optics. Currently, we offer a few distinct options for magnifiers ranging from 3x to 6x magnification.  

Our 3x LER Gen IV Red Dot Magnifier and SLx® 3x Micro Magnifier are great 3x magnification options. The 3x LER magnifier offers a long eye relief and a wider field of view than previous generation models. It features an adjustable diopter ring for optimal focus and weighs in at 7.9 ounces.  

A smaller overall package, our SLx 3x Micro Magnifier is our most popular magnifier. It retains the key features of our other 3x magnifiers, but weighs considerably less, coming in at only 5.3 ounces—the lightest in our collection. It’s also compatible with popular mounts like the Unity Tactical FAST Mount, which has a variant specifically designed to fit this optic. 

In addition to our 3x magnifiers, our GLx® 6x Magnifier is another high-quality option that’s optimized for longer range shooting. Currently, this magnifier has the highest magnification level we offer. It features a rugged flip mount, high-quality glass, long eye relief, and a wide field of view. Being a 6x magnifier, it does have a larger size compared to smaller 3x models, but it’s still lightweight at 7.2 ounces. 

Something else we want to mention is our SLx 3x Micro Magnifier and GLx 6x Magnifier models are unique in that they’re compatible with 1x prism scopes, specifically our SLx 1x MicroPrism™ scope. Not every magnifier is compatible with prism scopes, and when they are, they’re only compatible with certain 1x prism scopes. If you plan to use a prism scope with a magnifier, we recommend checking the compatibility charts before buying. 

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EOTech is renowned for its production of high-quality holographic sights, a staple sight option amongst enthusiasts. Like most other reflex sights, EOTech’s holographic sights aren’t offered with any level of magnification, but EOTech does have a line of magnifiers to complement their optics.  

Currently, EOTech produces three magnifiers, the G33, G43, and G45. The G33 is a 3x magnifier that is by far one of the most popular magnifiers around. Adding to its popularity, it was selected by US SOCOM for use in military applications. Like most magnifiers, it has an adjustable diopter ring, is made from durable materials, and often comes with a quick-detach cam mount. 

The G43 is another 3x magnifier that retains all core features as the G33, but comes in a much smaller package that weighs less. Despite its smaller size, it’s still an incredibly durable magnifier, as it’s built to the same standard as EOTech’s other models. Lastly, the G45 is EOTech’s 5x magnification offering. Even though it boasts a higher magnification level, it shares the same size and weight as the G33 and comes with the same features.  

As we said before, EOTech is one of the premier manufacturers of optics and magnifiers, and as such, they’re some of the more expensive options around. Depending on the model you choose, they can run anywhere from around $500 to upwards of $600, but rest assured, you’re getting a fantastic magnifier for the price. Each option pairs excellently with EOTech’s holographic sights, and they even offer packages that include both optics and magnifiers too. Even if you don’t run an EOTech optic, their magnifiers pair well with most of the popular reflex sights on the market.  

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Vortex Micro 3x Magnifier 

Vortex Optics is one of the most well-known optic manufacturers in the industry. Though they’re most known for their variable power optics, Vortex also produces red dot sights and magnifiers to accompany them.  

Their Micro 3x Magnifier is a popular offering. One of its main advantages is its low-profile design and light weight. Weighing only 6.9 ounces, it comes standard with a reversible cantilever flip mount and has a 2.64-inch eye relief. 

While this magnifier pairs exceptionally well with Vortex’s red dot sights like the StrikeFire II and SPARC, it can work well with any red dot sight that mounts at either absolute co-witness or a lower 1/3 co-witness. It isn’t compatible with every optic variant though, as the Micro 3x can’t be used with 1x prism scopes. Still, this magnifier is a great pairing for reflex sights and is usually priced around $300.  

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Holosun 3x Magnifiers 

Holosun is an incredibly popular manufacturer that specializes in creating durable reflex sights for rifles and pistols. They also offer a wide assortment of accessories for their optics as well, including magnifiers.  

One such option is their HM3X 3x magnifier. It’s a fantastic option that pairs exceptionally well with Holosun’s optics. It offers a 2.75-inch eye relief, a reversible flip mount, and features an adjustable diopter ring to precisely dial in your focus. Compared to other magnifiers in this list, the HM3X is larger, weighing in at 9.8 ounces while also having a longer optic tube. Still, its durable aluminum construction makes it resilient to wear and tear, and it also fits most budgets, as it’s commonly priced around $200. 

If you have a bit more budget, there’s a premium variant of the HM3X 3x Magnifier that is made with titanium. Titanium is a durable yet lightweight material, making it a great material for optics. The HM3XT magnifier keeps all the same features as the standard model but has a shorter length. Keep in mind that since titanium is a premium material, this optic costs more than the standard HM3X, being priced around $300.  

Each magnifier pairs well with Holosun’s full-size optics, such as the 510C open-emitter reflex sight, or their HS530G red dot sight. In fact, the HM3X magnifier is often sold in a package that includes the 510C.  

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Choosing the Best Red Dot Magnifier Combo 

While most magnifiers can be used with most reflex sights, there are some key factors you’ll want to consider before making any purchases. Any time you’re looking at optics and accessories to go with them, they can be a costly investment, so it’s important to take time to consider what’s available to make sure it’s compatible with your setup.  

Take mount height, for instance. Your magnifiers mount height needs to match up with the mount height of your optic. For instance, if your optic has a 1.93 mount, your magnifier also needs a 1.93 mount. If not, you won’t get a proper magnified sight picture, and your magnified sight will essentially be useless. Fortunately, most magnifiers come with different risers for different optics. This isn’t always the case though, as manufacturers tend to design their optic magnifiers around their specific optic models, so it’s smart to double check the mount heights before buying. 

Besides mount height, you should also consider the mount type. The most sought-after type of mount for magnifiers is a cam mount. As we’ve mentioned before, cam mounts use a cantilever system to swing it out of the way of the optic. While the magnifiers mentioned above each come with a cam mount, not all magnifier options do. So, if this is a feature you want, it’s important to check to see if the magnifier you want comes with one.  

Final Thoughts 

Adding a magnifier to your red dot sight setup can significantly boost its versatility, blending the benefits of variable magnification optics while keeping the compact, lightweight form-factor of a red dot sight. Running a magnifier in tandem with a red dot sight is a fantastic way to maximize the value of your optic, making it easier to consistently land shots on far away targets.  

Still, while magnifiers can be a great addition to your rifle setup, there are always additional factors to consider. It’s important to take your rifle’s barrel length, caliber, and purpose into consideration before making any purchases. For instance, a 3x magnifier is an excellent choice for most 5.56 NATO AR-15 rifles. But, for rifles configured for longer distance engagements, opting for a higher 6x magnification would be more helpful.  

After considering these factors, you’re ready to search for your new reflex sight magnifier. Whether you opt for one of our magnifiers, or another one that isn’t mentioned in our list above, so long as it fits your needs, it will be the best magnifier for your purpose.