The iconic AR15 has been a dominant force in the commercial market since the suspension of the Federal Assault weapons ban. As has often been the case throughout history, a military rifle has been converted for civilian use. Not only has the rifle been adopted, so has the red-dot sight, a great tool for close and fast shooting. Honing in on your target is faster and easier because theses scopes use a red-dot as the aiming reticle. This eliminates the need to keep a front-sight aligned with a rear-sight.
Quick Take: Top 3 Red-dot scopes for the AR-15
- Sightmark SM26008 Ultra Shot Plus Red Dot Sight
- Dagger Defense DDHB Red Dot Reflex sight
- Vortex Optics - Sparc Ii Red Dot Sight
Are Red Dot Sights Really An Upgrade?
The debate over red-dot vs. iron sight has probably been settled, with red-dots coming out ahead. A 2010 study at Norwich University in Vermont showed that red-dot scopes had a substantially higher percentage of hitting the target than iron sights. Granted, the study was done with pistols, not rifles. But it’s reasonable to expect similar numbers. Various close-range distances were tested, as well as moving and stationary targets.
While the name red-dot is commonly used, the actual dot produced by the sight is often green. These sights could be holographic or reflex sights, as well. The holographic sight is illuminated from the front of the lens, and a LED light is projected onto the viewing window to create a holographic red-dot. Reflex sights are simpler sights containing just a concave lens with a metallic coating that only reflects red light. The light is produced by a LED mounted inside the tube of the scope.
The reflex site is definitely the elder statesman, being 30-plus-year-old technology. Generally, reflex sights are the bare basics and just have an objective window to see through. But since they consume much less energy than holographic options, they are used more commonly by recreational shooters and sportsmen.
While red-dot sights help with a much higher accuracy rate when aiming at a moving target, they are typically not used for precision shooting. Their 2 to 4 MOA dot covers a significant portion of the target at a distance. In fact, it might cover a 2 to 4 inches spot at 200 yards. However, you do get a broader field of view than tube-style sights. You also have unlimited eye relief that allows for more peripheral vision. These factors make the red-dot sight perfect for fast target acquisition in close to mid-range.
Since the majority of reflex sights are not magnified (zero power / 1x), they are small, lightweight, and priced well. The military has recognized the value in this. The lack of magnification allows the operator to keep both eyes open (the natural way), maximizing their performance in tactical simulations and situations.
Red dot sights also enjoy the collective benefit of a lower price compared to other optics types, making it a very tempting opportunity for the private consumer. Simplicity and compactness make red-dot sights versatile so they can be sported on any weapon platform from rifles, shotguns to handguns, and even compound bows. The red-dot sight can be utilized for hunting or target practice. It can also be used for target games like trap, skeet, and sporting clays mounted on shotguns. Of course, it is also useful for home defense scenarios.
There’s no doubt that a red-dot is faster on target than a set of stock metal sights. It’s easier to use than a traditional magnified optic, too. But like every electronic device, it’s dependent on batteries. Nowadays, the higher quality red-dot sights come with long-lasting batteries that promise up to 5 years of continuous use, as long as you use the power-saving features such as auto-brightness and auto-power-off when not in use. Still, a lot of people still prefer to keep both a red-dot sight and their iron sights in case of sight damage or battery drainage.
The patterns of red-dot sights vary in range from a single dot to crosshairs, or even bullseye patterns, but these can degrade target acquisition. As we already mentioned, they aren’t necessarily red, even. Green is a common alternative.
What many people may not know is that red-dot sights are also affected by parallax. Since it’s used mainly in close-quarter situations, this doesn’t matter most of the time. But your aim could be affected at longer distances. Some major manufacturers try to overcome parallax “error” by using a concave reflecting lens.
Red Dots for Beginners
The number of people equipping their AR platform with reflex or holographic sights has increased substantially in the last few years. As you would expect, most manufacturers have climbed on the AR bandwagon offering a plethora of sturdy and functional AR specific optics that are interchangeable on different AR-15 weapons.
There’s a debate about whether a novice shooter should learn to shoot with a red-dot sight. We’re not going to take sides because we don’t want to upset anyone. But let’s just look at the two schools of thought.
Those who favor red-dots for beginners focus on the ease of use, and the likelihood of keeping the newcomer interested. Since it’s easier to learn and the likelihood of hitting the target is higher, they say, using a red-dot is a much less frustrating experience.
On the other hands, many people say that’s it’s important to learn “the right way” using iron sights. Knowing the basics will make them a better all-around shooter. And they’ll always be able to fall back on this skill if the optics fail.
Red Dots for Competition
The use of electronic red-dot reflex scopes is also on the rise with competition shooters.
AR-15s are ubiquitous at 3-Gun competitions. Of course, different divisions have their own rules for the use of red-dots, but when it’s permitted, the competitor should use a sight with the proper dot diameter. Smaller diameters are the best for bullseye, and a larger dot size is more suited for events that require moving from target to target.
Quick Comparison Chart of the Best Red Dot Sights
Vortex Optics - Sparc Ii Red Dot Sight
Rhino Tactical Green & Red Dot Sight
Burris - Fastfire Iii Red Dot Reflex Sight
Dagger Defense DDHB Red Dot Reflex sight
Sightmark SM26008 Ultra Shot Plus Red Dot Sight
Reviews of the Best Red Dots
When looking for a good red-dot sight, we take into account both quality and price. A good red-dot sight is going to be cheaper than almost any scope. With so many red-dot sights available at various price points, you have to choose between a reputable name with a higher price tags and an inexpensive or budget red-dot sight. But even these are perfect for plinking guns. There isn’t always a correlation between price and quality in this case.
The Sightmark Ultra Shot is ideal for someone looking for a cost-effective sight that’s versatile enough to mount on shotguns, handguns, or rifles. The selling point of this model is four reticle patterns in a combination of 3 MOA dot with 50 MOA circle in red or green.
The sight features simple commands in the form of two soft tactile buttons on the left side with the addition of a rotary switch for changing the reticle patterns.
The Sightmark Ultra Shot has five brightness settings. When using the automatic shut-off feature, you can get 2,000 hours out of the battery. This is a very durable sight built with an aluminum frame and metal shield. Its double-panel lens helps eliminate parallax, making it an alternative to overly expensive MIL-SPEC models.
The Dagger Defense DDHB reflex sight is another inexpensive AR-15 red dot. But it’s highly rated by users for its sleek styling and more importantly its rugged functionality. This is a reflex sight optic made with aircraft-grade aluminum. It offers a choice of four illuminated reticle configurations including a simple dot and a crosshair.
The product is easy to zero in. Even better, it still holds zero after a couple hundred rounds thanks to its locking screws.
As one of the most budget-friendly reflex sight, it can co-exist with standard AR iron sights. This top contender for the best low-range red-dot sight features a wide 291-degree field of view. This will be great for 3-gun competitions.
However, this entry-level small sight is water resistant, but not submersible
Another red dot from the top of the budget price-range sights comes from Vortex. This model gets the impressive name “Speed Point Aiming for Rapid Combat” - SPARC for short.
This is an exceptionally sturdy, tube-style red-dot sight. It has a fully multi-coated lens and a simple adjustment of the color, shape and illumination of the reticle. The device has 10 levels of 2 MOA red-dot brightness intensity. It also features a practical built-in brightness intensity memory function. With a six-hour auto shutdown feature, the battery life can last up to an incredible 5,000 hours.
FastFire III is the flagship product of an extensive selection of Burris red-dot sights. This third generation of the Burris FastFire family features an upgraded and complete shock and waterproof housing. It has a top-mounted battery (CR1632) for more natural battery replacement.
The Burris has a power button with three levels of brightness. It offers 1x magnification for both-eyes-open shooting, allowing perfect eye balance. The windage and elevation can be adjusted with clicks, just like a traditional variable-magnification scope.
Since the Burris FastFire III is even smaller than the Bushnell TRS-25, this micro red-dot can be used as secondary optics on an AR15 rifle. This little jewel is priced just above the line what would be ordinarily considered a budget sight.
The Rhino Tactical is a tube-style sight that comes with a 4 MOA dot in either green or red. It’s a sturdy model among the lower-priced AR-15 red-dot scopes.
As you would expect, this sight has no magnification. It features a 35mm-wide objective that provides fast target acquisition in most shooting conditions.
Using the Picatinny cantilever mount included in the package, this site is great to use alongside standard-height A2 front sights.
While it has five brightness levels to choose from, the Rhino often seems foggy or pixelated in low-light conditions.
Where Should the Red Dot Site Be Installed
When a gun owner has selected a red-dot sight that fits his AR15 and his specific need, the next step is to mount the new onto the rifle.
The prevailing thought is that the optimal position for a red-dot sight is the forward portion of the upper receiver. This point offers a better field of vision as well as being the most secure part of the gun.
If red-dot is placed at the rear end of the rifle, too close to the shooter, it leads to diminished peripheral vision when looking for a target or prey. On the other hand, placing it at the other end of the rail is no better.
For mounting, common advice is to get the sight as close to the bore as possible. The mounting rings should not be placed directly over the lenses - they can compress the tube and cause lenses to crack under recoil. To take the strain of the recoil off the tubes, you should position the forward ring as close to the center of the sight body as possible.
Adjusting the sight is easy to learn. There are just two screws installed opposite the coil springs for windage and elevation. Good old-fashioned experience is going to have to substitute for hash marks and holdover positions for compensating for bullet drop, though.
We hope we’ve shown you some of the highlights of red-dot sights as well as drawbacks. By now you probably know that if you want to reach out and touch something, then you'll need optics with plenty of magnification and real reticles. But if you are a recreational shooter doing some target practice or are simple interested in close-range uses of the gun, a red-dot sight should be a great sighting piece for you.
Red-dot scopes are definitely a trending accessory. The technology in a modern red dot is robust and straightforward, making them cheap to manufacture. No wonder why these simple devices are gaining so much traction in the gun world! If you are interested in reading more about other AR-15 scopes read our buyers guide here.