What if told you there was one upgrade you could apply to your AR 15 you could make that would allow you to shoot further and shoot more accurately? On top of that what I told you with this one upgrade you could shoot faster and more accurately?
Would you be interested?
Of course, you would. So, this one upgrade is a bit predictable, it’s an optic! An optic being either a scope or red dot. Both are easily one of the most important upgrades you could ever make to your rifle.
We are currently in a buyer's market when it comes to optics of all kinds. More companies than ever are producing scopes for long range shooting, sniping, and hunting. The same could be said for red dot companies producing red dots for close quarters fighting, home defense competition shooting, and even for hunting.
With the AR 15 being the most popular rifle in the United States a vast number of these optics are produced for the AR 15. They take into account AR sights, barrel length and caliber. AR 15 owners have more optic selections than any other group of shooters in the world.
So, the real question is which one is the best AR 15 scope for you?
Before we can answer that specifically we need to consider a number of factors. Trust me it’s not near as simple as you just tossing an optic on your gun and hitting the range. With so many options out there, we really have several considerations we must make.
Table of Contents
- How to Choose Between a Scope and Red Dot?
- On Red Dots - Choosing Your Best Red Dot for AR 15
- On Scopes - Choosing the Best Scope for AR 15
- Features to Look for in Both Red Dots & Scopes
- Top 5 Best AR 15 Red Dot on the Market
- Best AR 15 Scopes: 5 Best Rated on the Market
How to Choose Between a Scope and Red Dot?
So, the first question is do you need a red dot or a magnified scope? If you're not sure it’s important to understand the differences. A scope is magnified optic. This means you have the ability to see farther than the naked eye.
Scopes will often place you right on top of a target. They allow for easy observation and give you the ability to see your target clearly at a variety of distances.
A red dot is a smaller, lighter optic that is used for close quarters shooting. Red dots are built around speed rather than precision. A red dot optic does not have magnification unless you add an additional accessory. Red dots allow fast transitions between targets and the illuminated reticle is easy to easy while moving and shooting.
The real question you have to ask yourself is what is your rifle for?
A home defense rifle would be better outfitted with a red dot than a magnified scope. Inside a home the non-magnified red dot is the superior choice. Red dots are also handy for new shooters who haven’t had a lot of time behind a gun.
All it takes for a new shooter to score a hit is to put the red dot on the target and pull the trigger. Red dots tend to be lighter weight, and if weight savings is a desire then the red dot is the way to go.
Precision shoot is clearly a sport and hobby that requires a magnified optic. Magnified optics are also better suited for hunting game both large and small. With an optic you can clearly see your target and make sure you are taking a legal animal. Magnified optics are a must if you are attempting to shoot small targets.
I know right now you still aren’t sure what route to go, and that’s fine, trust me it’s a big decision. Keep reading because we are going to dive even deeper into the world of red dots and scopes. This way when you leave here you can make an informed and educated decision.
Not only are we doing a full buyer’s guide for scopes and red dots, but we are also including the suggestions of our team and their experience with a variety of scopes and red dots.
On Red Dots - Choosing Your Best Red Dot for AR 15
Red Dot Optic Size and Shape
Red dots come in what’s essentially three different sizes. Each size has its pros and cons and we’ll explore those.
The standard or full sized red dot is often the primary weapon sight for a dedicated fighting gun. These larger sites offer a wider field of view and are quicker and easier to get behind in stressful situations. A standard red dot is most often used by military and police forces.
A standard red dot will often offer the longest running battery, the more brightness adjustable setting, be the most durable option, and offer the most accessories. Standard sized red dot sights have an objective lens between 26 and 32mms.
The compact red dot sight is the choice of shooters who want to minimize the profile of their weapon, while retaining an easy to see and easy to use sight. The main advantage comes from weight savings and an often lower price. Compact red dot sights are 25mms and under for their objective lenses. Compact red dots have a smaller level of compatibility with accessories.
Miniature red dots are ultra-small and often rectangular or square shaped rather than round. These super small red dots rarely appear on ARs, but can be the choice of someone looking to build an ultra-lightweight gun. These are especially handy on AR 15 pistols due to their remarkably low weight and profile. Their open top design also makes them easier to use when you can’t rock a stock.
Square Shaped Red Dots
Lastly there are square cut red dot sights by companies like Eotech and Sightmark. These big bad boys utilize a square shaped design that some shooters may prefer. Square designs are often thinner around the edges that provides a wider and less interrupted field of view.
Reticle size is often measured in MOA. MOA is a measurement that allows you to estimate the size of your reticle when looking at distant targets. Basically 1 MOA is 1/60th of a degree and covers roughly 1 inch of a target at 100 yards. So, a 6 MOA reticle is going to cover 18 inches of a target at 300 yards.
Red dots designed for close quarters will often feature large reticles that are easier to see and faster to snap on target. Red dots designed for longer range shooting will feature a smaller reticle, so you can still see your target when its a few hundred yards away.
Choose the dot based on the range you are planning to use your gun. 2 MOA red dots are the most common for full sized rifles. They are big enough to easily see, but small enough not to distort a target for longer range shooting. When you go with a miniature red dot for close range shooting it’s not uncommon to see 6 to 8 MOA sized dots. These big and bright dots are perfect for snap shooting, and quick reactions.
Eotech’s unique reticle bears mentioning as well. It uses a much more complicated design that involves a wide 68 MOA circle with a 1 MOA dot inside the large reticle. This is designed for both close and distant shooting. It’s quite versatile and unique to Eotech optics.
There are many accessories you may consider when choosing a red dot optic. Some are compatible, and some are not. The first accessory is going to be a magnifier. A magnifier is a device placed behind the red dot and ads a level of magnification.
The two most common magnifications are 3x and 5x. These give you the ability to see further and clearer than a red by itself. They are fixed power devices and can be quite handy for longer range shooting. Most will only function with Standard size or compact red dots.
The next accessory is going to be night vision compatibility. Some optics will have, and some will not. It’s determined by both size and the reticle’s brightness level. A special extremely low setting is required to work with night vision.
If your red dot is night vision compatible it will have night vision settings and the manual should notate this. Size is another consideration and with miniature red dots you’ll be forced to wear the device with a helmet to utilize it with a miniature red dot.
On Scopes - Choosing the Best Scope for AR 15
Scopes is the term we use for optics that feature a built-in amount of magnification. Scopes are used for shooting more distant or smaller targets. They are used for spotting, and scouting a target as well. Scopes on ARs can be used for anything, from hunting to precision target shooting at that point. ARs are excellent marksman rifles and can be used in a variety of roles for tactical and competition shooting. Variable optics are quite popular in sports like 3 Gun. A type of AR 15 known as a special purpose rifle is designed for precision and long-range shooting and certainly needs a high end tactical scope.
Magnified scopes are quite complicated and again we are here to guide you through the process.
Scope Magnification Range
So how powerful of a scope do you need?
Is bigger always better?
Bigger isn’t always better and scope magnification will depend on how far you are shooting and what you are trying to shoot. Bigger is better is a poor mentality when it comes to the AR platform. The AR 15 uses the 5.56 round which is typically given a max range of 500 yards. Some marksman can stretch that range to up to 800 yards, but the round experience a significant loss in power at that range.
Step 1 is to determine the size of your target. The larger the target the less magnification you’ll need. For hunting animals as small as prairie dogs you’ll need something much higher powered than you’d hunt deer with. The general rule of thumb is the smaller the target the more magnification you need. For hunting prairie dogs, you might need a 15 to 20 power scope, for deer 3 to 9 power is outstanding.
Step 2 in choosing magnification is going to be determining the range you are shooting at, while considering the size of your target. Anything up to 500 yards on a man-sized target can be settled with a 4-power scope and proper shooting fundamentals. Having extra magnification to a degree can be handy for scouting or taking a more precise shot, but too much results in a heavy and expensive scope. For long range, small target shooting you’ll need that powerful 20x scope.
For tactical or action shooting competition you may want a low to moderate power. Being able to set the scope to 1x is great for close quarters shooting and then throwing it to 6x for those long-range engagements.
There are two types of magnification designs. Variable and Fixed power.
Variable power scopes are scopes that allow you to switch the magnification at will. They are often labeled in a manner that shows their max and min magnification range. For example, 3-9x means the scope’s lowest power is 3x and its highest is 9x. In between you can still use 4x, 5x, 6x, etc.
Variable scopes are great if you are planning to shoot a variety of targets at different ranges. They allow a shooter to be more versatile and gives them a greater variety of options.
Fixed power scopes are locked in at one range. They tend to be lower powered optics like the ACOG, but not always. Fixed power optics are great due to their simplicity and often inherent durability. Fixed power scopes lack versatility but make up for it in simplicity and smaller size.
When it comes to red dots your reticle choices are limited, but with scopes the sky is really the limit. There are tons and tons of different intricate and simply designs, so we are only going to touch on the most basic.
Mil and MOA Dot
Mil and MOA scopes are very similar. MOA and Mils are measurements that are used to help estimate wind and bullet drop. They are different measurements, which translates to different wind calls and drop calls, but they have the same purpose. These dots are designed to allow you to compensate for wind and elevation. Let’s say I am shooting a target at 400 yards with a Mil dot scope. I have a series of Mils that run left to right for windage and up and down for elevation.
Bullet Drop Compensating
Bullet drop compensating, or BDC reticles, are designed and calibrated to a barrel length and ammunition type to represent bullet drop. Each hash mark on these scopes represents a particular yard or meter range that bullet will drop. This makes it incredibly easy to compensate for longer ranges and much more intuitive than MIL dot scopes. The main issue is being stuck with one particular round.
BDC reticles are very easy to use, and are great for combat shooting due to the speed in which you can engage a target.
A basic crosshair reticle is just that, a simple cross hair without any hashmarks, mil dots, or moa dots. These simple crosshairs are most used on scopes designed for shooting around 200 yards where drop isn't a major issue. These simple scopes are affordable and often quick to use for close to moderate range shooting.
Variable scopes come in one of two focal planes, first focal plane and second focal plane. These terms are commonly abbreviated to FFP and SFP and for brevity’s sake we’ll do the same. This only applies to variable scopes as it has to do with how the focal plane affects magnification.
First focal plane scopes feature reticles than change in size as the magnification increases. With second focal plane scopes the reticle stays the same size and the target grows. This may not seem like a big deal, but it becomes important when you begin compensating for bullet drop.
SFP scopes feature a reticle that remains the same size as the target grows. SFP construction is simplified and often more affordable. SFP scopes are better suited for scopes that lack any form of bullet drop or windage compensation reticle. Due to the fact the reticle doesn’t grow when the magnification is increased the ballistic drop measurements are not accurate at all magnification levels.
Most often the MIL, MOA, or BDC hashmarks are only accurate at the highest level of magnification. Though this may vary, and the scopes owner manual should be consulted.
With a FFP scope the fact the reticle is magnified at the same rate the target is magnified means the space between the MIL, MOA, or BDC marks always remains the same. This means they are an accurate measurement at any level of magnification. This is better suited for tactical shooters who may be forced to shoot at any range.
Features to Look for in Both Red Dots & Scopes
Regardless of the type of AR optic you choose there are two features you need to look for in both options. These are durability and warranty.
A solid optic needs to be waterproof, shockproof, and fog proof. That's the absolute minimum. Let’s break each of those down briefly.
Warranty is going to be another major consideration. You want your optic’s investment protected and protected well. Always research the warranty and see what exactly it covers and how long it lasts, some scopes have certain warranties on electronics and others on optics.
Top 5 Best AR 15 Red Dot on the Market
#1. The Aimpoint COMP M4s
Aimpoint invented the red dot and has continued to perfect the concept. Since we are focusing on the AR 15 we are going to choose the Aimpoint COMP M4s. This optic was designed with the AR 15 in mind and was adopted by the United States Army as their general issue optic. The Aimpoint M4 is an energy high end optic that’s tough enough to go to war and come back, and even go one more time.
The Aimpoint M4 lasts up to 8 years on a single AA battery and is completely submersible. The scope is great for tactical and competition use. It’s also night vision and magnifier compatible, and co witnesses perfectly with an AR 15 height sights.
#2. Bushnell AR optics TRS 25: Best Budget Red Dot for AR 15
The Bushnell TRs 25 is a compact AR 15 sight that is designed around the AR platform. This miniature sight features a 25mm objective lens and comes with a riser to make it proper AR height. The TRS 25 weighs a mere 6 ounces and features 11 different brightness settings. It’s a simple and effective red dot that uses a standard CR2032 battery. The TRS 25 is a parallax free design, and is also water, shock, and fog proof.
The TRS-25 is perfect for close range competition shooting, and its small size helps keep the guns nice and light. It’s also at a great price with only under $100 and it's hard to beat the Bushnell warranty.
#3. Burris FastFire 3 Reflex Sight
The Burris FastFire 3 is a miniature red dot and is one of the best on the market. As a miniature red dot, it’s small, and weighs barely anything. The Fastfire 3 has a 3 MOA reticle and three different brightness settings. One of the most unique features is the automatic brightness adjustment feature. When set to automatic the red dot will automatically adjust the reticles brightness level to match the external light conditions.
The Burris FastFire 3 also offers a top of sight battery access for easy battery swapping, and is compatible with a wide variety of mounts.
#4. Vortex Sparc
The Vortex Sparc AR red dot sight is a budget priced full sized red dot sight from an outstanding company. Vortex produces fantastic optics, and this won’t be the last time we see them here. The Sparc comes with a mount and shim kit that allows the optic 1/3rd cowitness or absolute cowitness with AR height sights. The Sparc can last 300 hours at its brightest and 5000 hours at its dimmest setting.
The Sparc even features compatibility with night vision devices! The Sparc AR Red dot is an outstanding optic that’s an outstanding value.
#5. Eotech XPS2-0
It can’t be a great AR red dot list without tossing on an Eotech. The Eotech was designed and built for AR 15 and AR style weapons and feature an outstanding absolute cowitness. The Eotech Circle and dot reticle makes this a versatile and easy to use optic. The XPS2-0 model is the compact model, which is small in size, but big in value.
The Eotech XPS2-0 is lightweight, and compact, but still compatible with magnifiers. The XPS2-0 offers a nice and wide field of view and makes engaging moving targets nice and easy. The Eotech is currently in use by the Marine Special Operations community and has served overseas and been extensively proven.
Best AR 15 Scopes: 5 Best Rated on the Market
#1. Bushnell AR Optics FFP: Best Tactical Scope for AR 15
Bushnell’s line of AR optics have been generous to the AR 15 platform. These optics are built and designed around the world’s most popular rifle. The AR Optics FFP is an amazing tactical optic. It uses a bullet drop compensator dialed in for the standard AR 15 and 5.56/22 Remington round. The AR optics FFP is also a first focal plane scope that makes tactical shooting a breeze.
This is a variable scope with a 1 to 4 power magnification and uses a 24mm objective lens. To help you rapidly navigate that magnification range you get a throw lever that makes transitions rapid and easy. The reticle is illuminated and has 11 different settings. This is an excellent competition and tactical scope.
#2. For the Money: Vortex Crossfire 2
The Crossfire 2 is perfect if you are looking to outfit your AR 15 rifle for hunting. The AR 15 is a great hunting rifle, and topped with the right scope it can be a deer slaying machine. The Crossfire 2 from Vortex is a 2 to 7 power optic that takes advantage of the AR’s close and long-range potential. The Crossfire 2 is machined from a solid block of aluminum and is rigid and strong. It’s water, shock, and fog proof and built to last.
The Crossfire 2 uses a hash mark reticle for bullet drop and wind calls and are designed to be used at the 7 power. The Crossfire 2 is a lightweight, affordable, and well-made hunting scope that’s perfect for the AR 15 with just under $200.
#3. Leupold Mark AR MOD 1
The Leupold Mark AR MOD 1 is the scope for those who have or are building a Special Purpose AR 15. The Special Purpose rifle is made for long range shooting and therefore features a strong magnification range. This particular model is the 3 to 9 power model and is perfect for taking those long-range shots. Leupolds are favored by the military’s designated marksmen on their M16 rifles.
The Leupold Mark AR MOD 1 uses a mil dot reticle that was designed by the Marines. The Mark AR MOD 1 is a precision driven scope designed to give you the most accuracy possible.
#4. Trijicon ACOG
The ACOG is the chosen combat optic of the United States Marines and has served for over a decade and through two wars. The Trijicon ACOG is a fixed four power optic that is extremely compact and lightweight. It’s also one of the toughest optics on the market and provides an illuminated battery free reticle. The mix of fiber optics and tritium forms a solar like power source that brightens the reticle.
The Trijicon ACOG scope features one of the best bullet drop compensators in the business. It goes all the way out to 800 meters and from experience I can say it's dead on.
#5. Primary Arms 3x Prism
If the ACOG is a little too expensive for you Primary Arms produces a similar optic. The Primary Arms Prism is a fixed power 3x scope that utilizes the ACSS 5.56 reticle. This is a bullet drop compensating reticle that allows you to reach out and touch a target with very little effort. The optic has 12 brightness settings and is designed with the AR 15 in mind.
It’s compact, reliable, and very easy to use. Best of all its priced substantially lower than the ACOG.
These are our top choices for the best AR 15 scope. The AR 15 is an adaptable platform designed for quick and easy shooting. With an optic you’ve added a force multiplier to your rifle. Remember, shoot quick, and shoot straight.