Whenever enthusiasts upgrade their pistols, a reflex sight is almost always one of the first additions they make to their setups. Since their introduction, pistol optics have gained immense popularity, offering enhanced target acquisition speed and accuracy, especially when under stress.
With optic technology continuously progressing, it’s more common to see enthusiasts and professionals running handguns outfitted with various pistol red dot and mini-reflex sights. As their popularity has grown, so has the number of options. Regardless of which optic you look at, they each fall into one of two categories: open-emitter mini-reflex sights and closed emitter pistol red dot sights.
Both optic options come with their own set of unique advantages, so they excel in different applications. However, if you’re new to running a reflex sight on your handgun, you might be wondering which optic is the best one to go with. Follow along as we go in-depth on the pros and cons of each one.
How Does a Red Dot Sight Work?
Before getting too deep into the differences between pistol red dot and mini-reflex sights, a common question asked by enthusiasts is, “how does a red dot sight work?”. At their core, both optic variants use an LED emitter diode to project light that’s then collimated onto and reflected off the optic’s lens, creating their reticle image.
However, enthusiasts often erroneously refer to both optics as red dot sights, when this isn’t the case—as their distinction lies in their respective designs. While both are reflex sights at their core, for a reflex sight to be considered a red dot sight, the optic needs to use a closed emitter design and two lenses, making closed handgun optics a pistol red dot sight. Open-emitter mini-reflex sights, as their name suggests, feature an open-emitter design and only one lens, so they aren’t really a red dot sight.
A straightforward way to think about it is like this: all red dot sights are reflex sights, but not all reflex sights are red dot sights. We go more in-depth on their differences in our reflex vs. red dot sight guide—regardless, both reflex sight options work in a similar fashion, but their respective designs make them better suited for different applications.
Open-Emitter vs. Closed Emitter
Open-Emitter Mini-Reflex Sights
Open-emitter mini-reflex sights are simple, lightweight, and easy to use, making them a more-than-viable choice for most applications. Their open-emitter design gives them a wider field of view compared to closed pistol optics, providing a greater overall sight picture and a wider FOV. As such, they’re a solid choice that can greatly enhance your target acquisition speed and situational awareness. As a bonus, open-emitter mini-reflex sights tend to be more budget friendly, though this varies from model to model.
However, having an open-emitter design is a bit of a double-edged sword. Despite their inherent benefits, the emitter diode is susceptible to becoming occluded from dust, dirt, or any other debris in your environment. Additionally, while these optics are made to be durable, they don’t offer the same degree of rugged durability as closed optics. This makes them less suitable for use in extreme conditions, though for applications like recreation, competition, and personal defense, they’re definitely worth considering.
Closed Emitter Pistol Red Dot Sights
An increasingly popular option, closed emitter pistol red dot sights offer more rugged durability than open-emitter options. By using a more robust closed design, the emitter diode and other core components of the optic are kept safe from dirt and debris. These optics are often designed to be as durable as possible, so they’re more resilient to shock, fog, and water exposure, making them one of the foremost choices for professional use in harsher environments.
Still, they have their disadvantages, such as their constricted field of view. By having a closed emitter, the FOV size of these optics tends to be narrower compared to open emitter optics with wider lenses, and their reinforced optic bodies are often bulkier and slightly heavier as well. Moreover, because of their extra components and enhanced durability, pistol red dot sights tend to cost more than open-emitter mini-reflex sights. Still, despite their disadvantages, their robust construction and enhanced durability makes closed pistol red dot sights a solid choice to consider, especially if durability is among your primary concerns.
Which is Best?
So now that you have an idea of how these optics stack up against each other, you might be wondering which is best. The truth is that there isn’t a definitive better option, since they’re both designed to offer better performance in different scenarios.
For many, an open-emitter mini-reflex sight is a more-than-viable possibility for most applications. They’re light enough to not weigh down your handgun, and their low-profile design makes them easier to conceal for EDC purposes. Plus, their wider field of view makes them ideal for dynamic scenarios that require quick target acquisition.
However, if durability is your priority, you can’t go wrong with a closed pistol red dot sight. Designed to withstand use in harsh conditions, they fully protect the emitter diode and the optic’s other core components. As such, these optics are a solid choice for everything from recreational use to more intensive competitive, duty, or other professional use.
Popular Open-Emitter Mini-Reflex Sight Models
Because of their popularity and inherent advantages over iron sights, it’s no surprise that there are a lot of mini-reflex sights to choose from. Below are some of the most popular choices:
Primary Arms Optics GLx® RS-15 Mini-Reflex Sight
Primary Arms Optics offers a plethora of solid optics, including a range of Primary Arms pistol red dots. Their GLx® RS-15 Mini-Reflex Sight being one of the most popular pistol optics offered in their lineup. Constructed from 7075-T6 aluminum, the RS-15 weighs only 1.11 ounces and is both waterproof and shockproof. Notably, the RS-15 comes standard with a GLOCK MOS compatible mounting plate out of the box and it can directly mount to most SIG Sauer P320 slides with the SIG Pro cut. It also comes with AutoLive®, a motion activated auto on/off function, to provide maximum battery life.
As far as reticle options are concerned, the RS-15 is available with either a 3-MOA dot reticle, or the venerable ACSS® Vulcan® reticle system which has a 3-MOA center dot as well as a 250 MOA outer circle that’s only visible when your aim is off-center. Depending on which one you choose, your optic will either have a battery life that can last upwards of 50,000+ hours, or one that lasts around 5,000 to 25,000+ hours depending on your brightness settings. Regardless, both have an incredibly long battery life.
Trijicon RMR
The Trijicon RMR has long been one of the most popular open-emitter mini-reflex sights on the market. Currently, the RMR is in its second generation, designated as the RMR Type II. These optics boast a long battery life and come with an assortment of reticle options, including a 1-, 3.25-, and a 6.5-MOA option. Additionally, it can be used continuously for up to four years, and with its forged aluminum housing, it’s a solid optic to consider for anything from recreation to competition and duty use.
Also, if you’re looking for more of an upgrade, the RMR HD is worth checking out. It comes standard with a much wider objective lens, it’s waterproof up to 66 feet, and it comes with a circle dot reticle option, making it a more rugged optic that’s better suited for use in adverse conditions.
Holosun HE507C
Another popular open-emitter choice is the Holosun HE507C. Holosun is one of the most prominent brands in the optic industry, renowned for blending utility with affordability. The HE507C is renowned for its long battery life and overall versatility. These optics come standard with an automatic shut-off feature and Holosun’s ShakeAwake™ motion activation for better battery life, and for even more energy savings, they also come with a built-in solar failsafe unit to keep the optic running, even if the battery is dead.
Traditionally, these optics come standard with a circle dot reticle, but there are select models that come with the Primary Arms Optics ACSS Vulcan Reticle system. Depending on which model you look at, the estimated battery life can vary, with standard circle dot reticle models lasting upwards of 50,000+ hours, and ACSS Vulcan reticle models lasting around 25,000+. While this is quite a difference, keep in mind that this approximates almost 6 or 3 years of continuous operation, respectively.
Popular Closed Emitter Pistol Red Dot Options
Just like with open-emitter optics, the popularity of their closed emitter counterparts has skyrocketed—so there’s a wide array to choose from.
Primary Arms Optics PLx® HTX-1™
New to the Primary Arms Optics lineup is their PLx HTX-1, an American-made enclosed emitter pistol red dot sight. While Primary Arms Optics has produced numerous open-emitter pistol optics, the PLx HTX-1 is their first enclosed option, and it’s packed with features that make it a solid optic choice for your pistol. Like the GLx RS-15, the PLx HTX-1 utilizes a rugged 7075-T6 aluminum construction, complete with narrow-band glass lenses finished with anti-reflective coatings. Additionally, it comes standard with AutoLive® motion activation for better battery life, and it uses a CR2032 battery too.
What makes the PLx HTX-1 unique is its mounting system. Every other optic in this list is compatible with a single mounting footprint, forcing you to use adapters to mount them to pistol slides with different footprints. The HTX-1’s patent-pending modular chassis system makes it compatible with almost all currently existing optic ready handguns. Not only does this mean you can use basically any optic-ready pistol you own, but because its mounting system gives it such a low centerline, it effectively cowitnesses with standard height iron sights. Another key feature of this optic is its reticle, as it comes standard with the ACSS® Vulcan® reticle system (or a basic 4-MOA dot, if you prefer).
Trijicon RCR
The Trijicon RCR is essentially a closed emitter version of the RMR. As one of Trijicon’s most rugged optics, the RCR features a robust construction that’s designed to stand up to the rigors of professional use. Like the RMR, the RCR is built from forged 7075-T6 aluminum and has a battery life that can last upwards of three years. Additionally, it’s both shock resistant and waterproof up to 66 feet, just like the RMR HD.
It’s currently only available with a 3.25-MOA dot reticle, but it’s still a versatile optic using the RMR’s mounting footprint and deck height, as well as a top loading battery for easier replacement. So, if you already run a pistol with an RMR compatible slide and are looking for a closed upgrade, the RCR is a solid pick.
Holosun HE509T
In addition to their stellar open-emitter mini-reflex sights, Holosun also offers a plethora of enclosed emitter options, with the HE509T being among the most popular. The Holosun 509T is an upgraded variant of the standard HE509, being constructed out of titanium instead of aluminum. Just like how you can think of the RCR as an enclosed RMR, you can think of the HE509T as an enclosed version of the HE507C.
The HE509T shares a lot in common with the HE507C, coming with an automatic shut-off feature, ShakeAwake motion-activation, and a built-in Solar Failsafe for optimal battery life. In addition to these features, this optic also comes standard with Holosun’s multi-reticle system, allowing you to freely switch between either a 2-MOA dot, open circle, or a complete circle dot reticle.
Steiner MPS
Known for producing top-tier optics, Steiner is no stranger to producing high quality optic systems, and this extends to their reflex sights as well. The Steiner MPS is a coveted optic amongst enthusiasts, well-known for its durability and overall utility. Constructed from forged aluminum, the Steiner MPS features a rugged design that’s waterproof, shock proof, and fog proof, all while staying lightweight.
The MPS comes standard with a 3.3-MOA dot reticle that’s currently only available in red, an automatic shut-off feature, and several mounting plates for various pistol slide cuts. Additionally, its battery life lasts upwards of 13,000 hours, so you don’t need to worry about your battery dying anytime soon. Overall, it’s a solid optic for anything from recreational to professional use.
Conclusion
Adding an optic to your pistol setup is one of the best ways to enhance your shooting experience. Still, with so many options available, it can be daunting to have to pick just one. Fortunately, each pistol optic fits into one of two categories.
On one hand, you have open-emitter mini reflex sights, which are renowned for their lightweight construction, wide fields of view, and simplistic designs, making them a solid pick for everything from recreation to competitive use. On the other hand, you have closed emitter pistol red dot sights, which feature more robust designs to make them better suited for applications demanding more durability.
You can’t go wrong with either option, but if you’re on the fence about which one to go with, it’s crucial to take your needs and intended use into consideration before buying. Ultimately, so long as the optic you’re looking at meets your needs, you’ll be good to go.
