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Struggling to pick the right red dot the first-time round? You're not the only one.
Should you go scope or dot?
Will a gun sight make a difference to your AR-15 setup?
How much will it set you back?
Don't get worked up trying to figure this all out alone.
Let us help narrow down the options with our lineup of the best red dot sight for AR 15 setups that prove their worth in the hunt and in the combat field.
Best Red Dot Sights for AR-15 in 2021 (Comparison)
|Aimpoint Pro Patrol Optic||CHECK PRICE|
|EOTECH 512||CHECK PRICE|
|Holosun HS510C||CHECK PRICE|
|Vortex Optics SPARC II||CHECK PRICE|
|Primary Arms SS Microdot||CHECK PRICE|
|Vortex Strikefire II||CHECK PRICE|
|C-MORE Systems Railway||CHECK PRICE|
|Sightmark Ultra Shot Plus||CHECK PRICE|
|Trijicon MRO 1X25 2 MOA||CHECK PRICE|
|CYCVIS 1x25 3 MOA||CHECK PRICE|
Red dots are available far and wide and the options are practically endless. They're no stranger to handguns or AR-15 (ArmaLite AR-15) and MSR (Modern Sporting Rifle) platforms, and most any red dot you choose would likely feel right at home atop your flat top receiver.
But, getting to where you're confident in your choice of red dot is the time-consuming, decision-flipping, and budget-stretching part that can make the process difficult.
To help you out, we narrowed down our exclusive lineup with only the most popular AR 15 red dot sights still available today. Often, the best red dots show up time and time again, and you can bet we've already taken note. Make sure you check out our Best AR-15 Scopes and Best Red Dot Sights lineups to see what other optics may catch your fancy.
We've tried to avoid the repetition of red dot models featured on our other lineups purely to provide more suitable options here. Variety is the spice of life, right?
With that variety comes several price points and a range of brands. But, what do they all have in common? They're highly ranked red dots and their reputations precede them. Does being popular have its perks? In this lineup, it does - it gets you seen!
The Best AR-15 Red Dot Sights - Reviews
1. Aimpoint PRO - Best for Patrol Rifle
The Aimpoint PRO (Patrol Rifle Optic) deserves to be featured on every red dot lineup - it is one of the best. It's been ranked and rated by real-time shooters including cops. As a patrol-ready optic, it has some serious grit for serious military use out in the field.
- 2 MOA red dot
- Long battery life
- Always on
- Compatible with other gear
- Transparent rear cap
- Quality control issues
As a mass-produced product, there's a slight chance you might get a red dot with a defect. With the few complaints that exist, it's been anything from red dot brightness issues to battery problems. The PRO is covered under warranty and guaranteed to be free of defects and this has proven true for hundreds of buyers.
The 2 MOA dot has 10 brightness levels with the first 4 levels being night vision device (NVD) compatible. Leaving it on setting #7 will ensure the battery lasts for 30,000 hours (approx.) - "always red - always on."
The PRO red dot is rugged and compact, weighs less than 12 oz with caps, mount, and spacer, and is easy to use - everything a law enforcement officer values in an optic. It also has speed on its side with its transparent rear cap design. For instantaneous use, raise your rifle while keeping both eyes open, and you'll have a red dot on your target.
Home defense, SWAT, duty, and patrol use - the Aimpoint PRO has you covered.
2. EOTECH 512 Red Dot Sight - Best Under $500
EOTECH specializes in extremely popular holographic weapon sights that fit the bill for our red dot sight lineup. EOTECH is a major brand in the optics industry among professionals, and they're known to cost a lot more than your average reflex sight. If this is a first-time buy for you, the 512 model is the best place to start as it's their most popular-selling sight.
- 1 MOA
- 20 brightness levels
- Battery life
Holographic sights are battery hogs, and this model is juice hungry. It takes 2 AA batteries, which tacks on a little poundage, and it lasts about 600-1,000 hours depending on your choice of lithium or alkaline batteries.
To save some of that precious battery time, set the 512 to automatically shut down at either 4 or 8 hours.
If you need to pair it with any NVDs, you won't find that capability here with the 512 model, regardless of its 20 brightness settings.
The open 68 MOA circle has a 1 MOA dot at the center and is designed for close-range and rapid-fire situations. It has 3 usable aiming points calibrated for .223 cal 62 gr cartridges - right up an AR-15's alley.
Built to satisfy the needs of tactical professionals, it's rugged (water and fog-resistant), has excellent glass optics and coatings, and is easy to use with its heads-up-display.
3. Holosun HS510C Reflex Sight - Best Under $300
This Holosun reflex sight is highly praised. Buyers and users deem it extremely durable, instantly ready, and the best red dot at its price point. Such high praise for such a little thing.
- Dual powered
- Shake Awake
- Multiple reticles
- Quick Detach mount
- Quality control issues
The HS510C reflex sight has a couple of interesting features that might sell you on it. The first is the Shake Awake feature that allows this sight to be left on and constantly ready. When not in use, the red dot disappears helping to conserve the battery. Move it, and it's "shaken awake" and ready for instant use.
The dual power option on this Holosun is automatic and manual brightness. The automatic mode is actually a solar-powered feature that adjusts the reticle's brightness according to ambient lighting conditions. While it sounds awesome, it might be too dim for your liking. Good thing the single CR2032 battery can deliver approximately 50,000 hours of use.
You also have multiple reticle options available with this reflex sight: 2 MOA dot only, 65 MOA adjustment ring only, or 2 MOA dot and 65 MOA adjustment ring. The reticle is powered by the same LED, so you won't have to re-zero between switching up reticles.
However, being able to use all these awesome features means getting a sight that functions as it should in the first place. Complaints include defective sights that won't power on or feature issues that are defunct. This sight is covered by Holosun's Limited Lifetime Warranty. According to the masses, you won't need it.
By the way, another great red dot sight under $300 is the Burris Fastfire III.
4. Vortex Optics SPARC AR2
The SPARC AR has Vortex’s greatest benefits - dependability, accuracy, and clarity. The AR2 model is an upgrade from the popular and highly ranked SPARC AR1. Just when you thought it couldn’t get better, it did.
- Multi-height mount
- 1x power 2 MOA
- 10 brightness settings
- Night vision compatible
- Long battery runtime
- No disabling auto shut-off
If you forget to power down your SPARC, it’ll automatically do it for you after 12 hours. Even though this is very helpful for those who don’t use their ARs often, it could be an inconvenience for some. The fact that there is no ability to disable the auto-off is a disadvantage, and with its extended battery life of 50,000 hours as an upgrade from the SPARC AR1, it should be a possibility. Maybe this could be a feature for a future model or upgrade? However, for most people, it’s not going to be a big deal.
The AR red dot is a 1x, parallax free unit with a 2 MOA dot – large enough for close quarter shooting and small enough for long distances. Like its predecessor, it has 10 variable brightness settings. The lowest two settings are night vision compatible.
The Vortex red dot is versatile with its multi-height mounting capabilities. It comes with a built-in mount that is designed to be set for lower 1/3 co-witness. Mount as-is, and you’re set to go. If you prefer an absolute co-witness, remove the 3mm base shim, and voila, you’re done.
Merely saying the SPARC AR2 is waterproof, fogproof, and shockproof would be an understatement. We all know how indestructible Vortex optics are – ‘nuff said.
5. Primary Arms Silver Series Microdot
The Microdot is this brand's best-selling red dot scope. It's mini, compact, and yet full of punch and value when put into action.
- 2 MOA
- FMC optics
- NVD compatible
- Quality control issues
It seems with mass produced products, there's bound to be a few, defective Microdots that will get out. Primary Arms has shown to be extremely responsive, and their Return Policy states they will repair your red dot but be sure to check out the 3-year warranty on it before you decide to buy.
The Microdot comes as a small, compact package: 2.54 inches long and only 5.4 ounces in weight and that includes the light-as-a-feather CR2032 battery. The battery provides up to 50,000 hours of usage, and with 11 settings, you'll want to use it on the medium setting to stretch that number.
It's also NVD (Night Vision Device) compatible on the lowest two settings, and with as little space as it takes up, throw a magnifier atop your receiver as well.
It comes ready to mount with a standard Picatinny rail that's also removeable, and you get a pair of bikini lens covers in the buy. Hardware and accessories aren't the best, but the red dot itself is solid and worth the price according to users.
If you want a mini sight at miniature cost with decent quality and tons of value, a Microdot may the only dot in your future.
6. Vortex Optics Strikefire II - Best for Hunting
Out for a little AR-15 coyote hunting this year? Trying to keep your options under $200? When high quality is important and the budget is tight, your options are limited. But, thanks to Vortex, you don't have to strike out of the nighttime hunt. The Strikefire II is a red dot you must consider.
- 30 mm objective lens
- FMC optics
- Battery life
You could say the battery life of 400-7,000 hours from max. to min. brightness is good, but it's not great when you see red dot battery life in the tens of thousands as an industry standard. But, the auto-off feature after 12 hours of non-use will help to spare some battery juice.
Even though the Strikefire II red dot sight is a compact at 5.6" long and weighs less than half a pound, it's not a microdot with mini performance. It has a large 30 mm objective lens and a 30 mm tube body to allow 100 MOA in adjustment travel and added robustness.
As is usual for a Vortex Optics, it's fully fog, water, and shockproof - completely rugged with its single-piece chassis body. With FMC (fully multi-coated) optics, the 4 MOA daylight bright reticle will be highly visible against a clear, unobstructed wide Field of View. With 10 brightness levels and 2 of those being NVD (night vision device) compatible, you can stay out and hog hunt to your heart's content.
When you buy a Vortex Optics red dot sight, you don't just buy the optic, you also get an unmatched warranty that's said to be the best around - ever. VIP service is more than very important person treatment. It's a Very Important Promise Vortex puts behinds their red dots.
7. C-MORE Systems Railway Red Dot w/Standard Switch
Competition shooters should know about C-MORE Systems as their sights are often the top choice for champion sharpshooters. But, even if you're not a 3-gunner, this Railway red dot will make an excellent home defense and range gun sight at much less the cost than an Aimpoint or EOTECH.
- 6 MOA
- Close-quarter shooting
- Interchangeable dot module
- Dual positive locking adjustments
- Polymer body
- Battery life
Being straightforward from the start, this is the polymer body Railway red dot. It's not robust enough to be considered combat-ready or bomb-proof, but chances are, it's not going to see any of that type of action. It's also what helps to keep the cost low, and it will hold up just fine for range work and any self and home defense use. Just don't forget to turn the C-MORE off since you only have 300-1500 hours of battery juice.
This model has the 6 MOA dot that’s made for close-quarter shooting. Want to change up the dot size at some point in time? No problem. The interchangeable dot diode allows for this feature if you decide you'd rather buy a different size red dot without buying a whole new sight. Since it's compatible with all weaver and Picatinny mounts, it can literally be put onto anything. On your AR-15, you'll be able to get an absolute co-witness with iron sights.
This Railway red dot also has the standard switch which is the dial rheostat that controls brightness intensity. While the click switch model has tactile clicks that you can always keep on the same setting, the rheostat can be fine-tuned for ambient conditions or what you think looks good.
The Railway red dot has a few, unique features of its own that makes it worthy of a spot in our lineup. It should be a contender on yours too.
8. Sightmark Ultra Shot Plus Red Dot Sight
It wasn't that long ago when the Ultra Shot saw some upgrades that were in high demand by users, and here we have the Ultra Shot Plus SM26008 red dot sight. Even with its improvements and added features, it's still under 100 bucks.
- Red or green dot
- Multiple reticles
- 1 hour shut-off
- Aluminum hood
- Slop in reticle switch
- Battery life
It's an entry-level red dot with some really good ideas. First off, it's priced real cheap. Secondly, it has an aluminum hood that provides added protection to the lens.
Thirdly, it also has an automatic 1-hour shut-off feature that comes in handy for all those who forget to turn their red dots off, in this case, everyone. You'll appreciate that 1-hour shut-off because you only get 1,000 hours of battery time.
Reticle illumination can be switched between red and green. This sight also offers multiple reticle options, however, there's a catch. The reticle dial has quite some slop to it when transitioning between reticles. This affects the display, and it also brings up zero and recoil concerns. Without a locking mechanism or less play within the reticle dial, you should zero with only one reticle option and disregard the others.
This red dot sight has a quick-detach mount, but it does protrude out to the left side quite a bit. For recreational use, the Ultra Shot Plus gets it done. It can be a worthwhile tool if you know about its quirks.
9. Trijicon MRO 1X25 2 MOA - Best Mini Red Dot Sight
It's a Miniature Rifle Optic (MRO) red dot. It may be small, but it has sass. Don't underestimate the small stuff.
- 2 MOA
The MRO may be a miniature optic, but its price tag is anything but. Never mind, we all know Trijicons are expensive, but they value something that not all other brands do - quality. Take their extremely popular Trijicon RMR for example.
The MRO is made with forged aluminum, no polymer plastic material here. It's also completely sealed and waterproof. Even with its robust and rugged build, it's still lightweight at 5.1 oz with the battery installed and mount. It's mini-sized at 2.6 x 1.7 x 2.18" with the included low mount.
The 2 MOA dot is crisp and bright, and you can change up the brightness intensity with the ambidextrous control dial on top of the sight. It has 8 total settings with 2 compatible with night vision, 5 for daylight use, and 1 extra bright setting.
Setting the brightness to intensity "5" which is level "3" in the daylight settings will get you 5 years of continuous use out of the single CR2032 battery. We can certainly say the little MRO has a lot of endurance for being on the short side. What did we say again? Oh yeah, it may be small, but it has sass!
10. CYCVIS 1X25 4 MOA Review - Best Value for the Money
- ⌖【High Image Clarity】 - Mini red dot sights with multiple anti-reflective coatings on all air-to-glass surfaces increase light transmission. Bright red dot display...
It may be an off-brand red dot, but it has price and functionality under its belt. For target shooting and range work, why spend more than $50 on a budget red dot?
- 4 MOA
- 11 brightness settings
- Battery life
- Lifetime warranty
- No riser included
The red dot itself is a solid piece of work. For a cheap, off-brand sight, it actually doesn't have much in the way of flaws. Sure, there may be a build quality issue with a one-off red dot, and the brightness knob has said to be a little stiff. Other than that, there are no real, consistent complaints about it.
It's completely covered with a lifetime warranty, and buyers have said customer service is excellent. Although no riser block is included (will have to be purchased separately) and the Allen wrench is often missing in the package for installation, the sight is cheap enough that you can buy those extra parts yourself.
The CYCVIS red dot has a 4 MOA dot with 11 brightness settings that will halo at max brightness if it's not appropriate for ambient conditions - but this is true of all red dots. It takes a 3V CR2032 battery that can provide over 50,000 hours of usage. For the price, it's impressive that it has multi-coated optics, scratch-resistant lens, and it's O-ring sealed and nitrogen-purged.
It's an unassuming sight at first, but it's by far the best 50 bucks you could spend on a red dot. Finding value where it's not expected is always a good buy. Others great buys include the Bushnell Trophy TRS-25 and the Sig Sauer Romeo5 red dot sights.
What to Look for in a Red Dot Sight for AR-15
Red dot sights are straightforward gun sights - just point and shoot. If you can see the red dot, you can hit the target. But, there are differing factors and features to consider that will guide you in your decision process.
What are you using it for? Do you need a larger dot to improve speed and target acquisition? Are you using the same red dot for everything from close quarter work to long-range shooting? Do you need the ruggedness and ease of use required for patrol and duty use?
Consider these red dot features as you attempt to add to the functionality of your weapons setup.
You'll see a huge range of price points in the red dot market. They're currently one of the most affordable optics you can mount to your AR 15. Many red dots under $100 are suitable for target shooting and plinking for recreational purposes, but they may lack the build quality to last and be used professionally.
The mid-range of red dots are often used for many things like hunting, range work, and even some law enforcement use. Red dots are equipped with precision and high-quality dots, and battery-saving features are also introduced here. This is where most buyers will be happy with their buy.
High-end red dots are often touted for professional use with the bells and whistles the industry has to offer while still being easy to use optics. Everything must meet the standard here from dot accuracy and build quality to being instantly ready and dependable. When buying for professional use, it's best to spend more for the better quality with proven optics that other law enforcement agencies use.
Red Dot VS LPVO
Low power variable optics (LPVO) are another alternative to red dots that are excellent additions to the MSR platform. It not only provides low magnification, but it also allows for higher power to stretch the distance in long-range situations. However, some LPVOs cannot achieve the true 1x power that red dots allow.
Plus, with two eyes open in close quarter work, the red dot reigns as the preferred gun sight. Red dot price points are also significantly cheaper than an LPVO, even for brands such as Aimpoint, EOTECH, Trijicon, and others.
Open VS Closed System
Red dot sights is more of a catch-all term for a range of gun sights such as holographic (eg. EOTECH), reflex, and prism sights. Reflex sights have an open system that allows for a small, often rectangular window to look through, but they also come in the closed, tube-style design also.
Between the two types of reflex sights, they essentially do the same thing - get your dot on the target with 1x magnification. However, size, weight, and battery life will vary between the two styles.
Prism sights look like tube-style optics, and they use a prism to provide an upright and right-way image. They're often best for those after a little magnification and extended shots. You'll also have to be conscious of eye relief/eye box measurements when mounting prism sights.
Is a 2 MOA, 4 MOA, 5 MOA or 12 MOA dot right for you? Your AR-15 is capable of taking shots not just at 100 yards, but out to several hundred yards (cartridge dependent), but what are you using it for? Typically, a smaller dot is desired for precision range work when you don't want to cover up much of your target at a longer distances.
A larger dot size is desired in close quarter applications when you need your dot on your target now. You need your eye drawn straight to the dot and the dot gets on your target fast and accurately around tight corners, in buildings, and within 25-50 yards.
Battery life will vary between red dot scopes and manufacturers. Red dots that draw more power will require larger and heavier batteries, and smaller red dots mightn't require that much. The most common battery used to power red dots today are the small, CR2032 batteries.
You will usually see 30,000-50,000 hours as the advertised battery life when setting dot illumination at the manufacturer specified setting. Some features can draw more battery life like max brightness settings and auto-shut down times and motion activated features can help to conserve it.
Not all red dot sights are compatible with other gear due to their design, size, and limitations. If you're planning on pairing your red dot with a magnifier or NVD (night vision device), be sure your receiver rails have the room for it, and that the illumination settings on the red dot are compatible with the NVD.
Win When You Go Red!
Red dots are here to stay and they're only getting better in design and quality while becoming more affordable. Some will always be better than the rest just like some brands will always rise above others. If you know what you want to get done, you can pick the right budget and the perfect red dot sight for you.
They're in-demand optics because they're fast target acquisition sights that allows you to enhance your shooting and accuracy over iron sights. But, many red dot and mounting systems still allow you the ability to fall back on your iron sights if you ever need to - it's a win-win. When you go red, there's no losing.