If you’re like most people, you probably started with an essential AR 15 but realized over time that you could upgrade the rifle to fit your needs better. With the modular system on the AR 15, upgrading its components is easier than it looks.
But, with so many different ways to customize, we’ve broken these AR 15 parts into several categories, including essential and aesthetic upgrades, functional upgrades meant to improve performance, and the most critical promotion of them all: yourself.
Tier 4: Handguards, Sights, Grips, and Slings
If you’re simply a beginner still figuring out their shiny new rifle, upgrading your handguards, sights, grips, or slings is an excellent place to start. You won’t significantly change how your AR performs, but these upgrades and accessories may improve the function and the rifle's appearance.
While handguards with mounting options are more standard on AR 15s than they used to be, there are still plenty of rifles with basic, plastic handguards that don’t allow mounting grips, flashlights, or lasers.
So, if you don’t have a rail system, switching to one is an easy upgrade for many beginners, but you’ll still need to pick out whether you want a free-float rail system or a non-free-float system.
While they may be more challenging to install, many people prefer free-float rail systems since they’re stronger, rigid and improve the overall accuracy of the AR 15. A free-float system doesn’t contact the barrel, so you don’t have to deal with barrel warping.
Non-free-float systems won’t improve accuracy, but they’re usually easier to install, more affordable, and won’t add too much excess weight to the rifle.
Once you’ve picked out your new rail system, you’ve still got to decide on one of three significant rail system designs and attachment styles:
- Picatinny: Picatinny rails are the oldest rail design and the heaviest. While its original design was meant for mounting optics, you’ll have no trouble mounting other accessories on a Picatinny.
- M-LOK (Modular Lock): As the newest mounting system, M-LOK rails have slots that let you mount your accessories directly or a piece of the rail for your addition.
- KeyMod: The lightweight design of KeyMod systems has made them extremely popular, and while they function similarly to M-LOK systems, a KeyMod system uses keyholes instead of slots.
The most accurate shots come when you’ve got the best sight.
With traditional AR 15s, you’ve got both a front sight and a rear sight. The rear sight features two ghost rings, a large pinhole for nighttime and a much smaller one for daytime. The traditional design had the rear view fixed to your carrying handle, which meant you needed to modify your upper receiver to remove the picture, although that’s not as common for AR 15s anymore.
With sight upgrades, many people start by upgrading their iron sights, which is much easier if you already have a rail system. Not only are iron sights typically more affordable, but you can upgrade rear and front sights separately. There’s no shortage of options available. Flip-up sights, for instance, are a popular option that gives you better long-range accuracy.
However, if you don’t mind dishing out a little more money, upgrading your optics with a high-quality red dot will provide better sight for nighttime shooting and faster target acquisition.
The AR-15 is a long, heavy gun; if you’ve got to carry it over any distance, a good sling can make all the difference. Slings help you handle the rifle when you’re not actively using it, so you can take some of that weight off your arms and focus on your destination.
There are a couple of different types of slings you can get for your AR 15, such as:
- Single-point slings: With a single-point sling, a single loop goes over your head, and the strap rests diagonally across your body. Single-point slings are more famous for military or law enforcement personnel since they allow you to grab the gun quickly from the resting position, but they aren’t great for weight distribution.
- Two-point slings: For anyone not in law enforcement or the military, two-point slings are the more popular choice. You can carry the rifle in multiple positions, and the adjustable loops allow you to set up a more stable, accurate shot. The only downside to two-point slings is that transitioning from one place to another may be awkward.
- Three-point slings: While you may see the occasional three-point sling, most AR-15 owners don’t opt for this type because it restricts gun movement and adjustment too much.
If there’s one thing that can distract even the best shooters, it’s a grip that doesn’t feel right. Rather than worrying about your shot, you’ll only be able to think about where to put your hands. That can affect the accuracy of your photo.
While modifying the grip on your AR 15 is an easy (and standard) upgrade; it’s also important. Some prefer rigid grips with fiberglass reinforcement, while others prefer smooth rubber with plenty of finger grooves.
A new grip can also come with other benefits depending on the type. For instance, you absorb recoil, reduce muzzle climb, and protect your hand against rail system heat.
Tier 3: AR 15 Muzzle Brakes, Flash Suppressors, Buffer Tube Kits, and Heavy Buffers
Muzzle brakes, flash suppressors, heavy buffers, and even buffer tube kits may not be aesthetic upgrades, but they can make a big difference in how well your rifle performs.
If you’re worried about recoil and muzzle climb, the right muzzle brake can make all the difference. Muzzle brakes are significant in keeping your barrel steady and reducing recoil. So you don’t have to adjust as much while you shoot. When you fire, an AR 15 muzzle brake redirects the gas that follows your bullet to vents on the side of the brake.
If you use your AR 15 for competitive shooting, muzzle brakes are often crucial for maintaining speed and accuracy.
If you’re using an AR 15 for nighttime hunting or prefer shooting at night, flash suppressors are almost a requirement. When you fire, a suppressor reduces how much flash comes out of your barrel, which makes it easier to conceal your location.
Other shooters prefer flash suppressors because that bright flash from the barrel can distract at night and even affect your vision.
Buffer Tube Kits/Heavy Buffers
While it’s one of the more intensive upgrades you can make for your AR 15, switching out the AR 15 buffer tube or using a heavy buffer can be great for performance.
The actual buffer on your AR 15 serves as a cushion between your bolt carrier group and a buffer spring. If you’re using the right buffer weight, you can minimize recoil impulse and extend the overall lifespan of your buffer.
If you don’t mind doing the work yourself, buffer tube kits have everything you need to upgrade yourself.
Heavier buffer weights are popular with AR-15s since they cause more resistance and allow the rifle to fire off a smoother shot. Of course, too heavy buffers can also cause problems because they may prevent the AR from cycling, messing up your ejection and extraction.
When it comes to picking out a heavier buffer, there are a couple of standard options:
- Heavy (H) Buffer (3.8 oz) – If your rifle has problems with extraction, you may opt for one of the heavy buffer models, starting at 3.8 ounces.
- H2 Buffer (4.6 - 4.7 oz) – If you have a mid-length gas system, H2 buffers work well.
- H3 Buffer (5 - 5.4 oz) – If you’re missing the traditional gas system in your AR and have a pistol caliber build, an H3 buffer can help ensure smoother action and reliability.
Of course, if you want to dial in on your AR’s performance, specialty buffer weights are between the standard Heavy, H2, and H3 buffers.
Tier 2: AR 15 Barrels, Triggers, and BCGs
Once it comes to upgrading AR 15 barrels, BCGs, and triggers, you’re making huge adjustments with considerable changes to performance and function.
Depending on your shooting style and what you’re using it for, there are multiple ways to upgrade an AR 15 barrel. For instance, longer barrels can provide a more accurate shot, but you’ll often get more versatility and maneuverability with shorter barrels.
The lining on your barrel can also make a lot of difference. Chrome lining on an AR 15 barrel protects the component against corrosion and extends the life span of the barrel. For competitive shooters, stainless steel may be the better option since it has less effect on accuracy than a chrome lining.
An AR 15 trigger with perfect resistance and comfort can significantly improve your shooting experience. So it’s no surprise that this is one of the first significant modifications that rifle owners like to make.
If you’re worried about firing your rifle in a high-pressure situation, like a home invasion, single-stage triggers ensure your rifle goes off when you pull the trigger. For competitive shooting or recreational shooting, two-stage triggers often work better.
When your AR 15 is malfunctioning, a common culprit is a lack of lubrication of your bolt carrier group or AR 15 BCG. The more you use your rifle, the more wear and tear you subject your BCG to.
Fortunately, there are plenty of ways to upgrade your BCG to ensure you get a reliable shot. For instance, with a nickel boron-coated BCG, you’ll get slicker components that don’t require as much lubrication.
You can also purchase AR 15-style bolt carriers in complete kits. Many owners appreciate the AR 15-style is lightweight and offers a higher shot speed. There are also M16-style bolt carriers that you can use to upgrade. These carriers are heavier and slower but provide better reliability and accuracy.
Tier 1: Upgrading Skill and Training
Whether you switch out your handguard, use a muzzle brake, or replace the trigger, the most essential AR 15 upgrade you can make isn’t to the rifle... it’s to yourself. Even top-of-the-line, high-quality upgrades and accessories can become useless if you haven’t improved your skill and training with the gun.
A professional shooter with an essential AR 15 will still outperform a beginner with all the fanciest upgrades. Training and skill will always matter more than accessories; the only way to get those upgrades is through plenty of practice.
Before you make any upgrades, it’s always a good idea for beginners to get comfortable with their rifles' traditional design and performance. Find out what aspects you like and which parts might not serve your shooting style well. Most likely, you’re not going to need (or want) to make all the upgrades on this list, but there may be a few components that you want to switch out.
Not all rifles may be easy to customize, but fortunately, the AR 15 isn’t in that category. From making easy adjustments like AR 15 handguards and AR 15 grips to AR 15 stocks and barrels, there is no shortage of ways to upgrade this rifle’s components.
However, investing in your skills and training is still the best way to change your performance, which comes significantly through practice. Practice won’t just improve how well you shoot but also help you understand which parts of your AR 15 need to be adjusted to fit your shooting style (and which ones don’t).