AR-15 Handguards are one of the most important parts of a rifle. They protect your hand from the extreme heat of your barrel and act as the hub for mounting accessories.
Being a critical component for the AR-15, it’s crucial to have a handguard that adequately fits your needs. Depending on how your rifle is set up, you may only be able to use one specific type of handguard unless you modify your rifle.
Notably, there are two distinct AR-15 handguard types: drop-in and free float. Even though both can, at times, have similar features, their construction and mounting type varies. Below, we’re breaking down the different handguards and which one you should use.
What is a Drop-In Handguard?
Drop-in handguards are made up of two halves that are, in most cases, mounted to the rifle via its delta ring. These handguards are commonly used on rifles that have a fixed front sight post or ones that don’t have a low-profile gas block. Because of their simplicity, they’re easy to install, making them an easy upgrade for mil-spec AR-15 rifles.
You’re likely familiar with the A2 style clamshell handguards that comes with many mil-spec AR-15s. Though they’re one of the most common drop-in handguard variants, they lack mounting surfaces like picatinny rails or M-LOK rails. While there are a lot of aftermarket options available, for the most part, drop-in handguards have similar pros and cons.
Pros
- Drop-in handguards can be some of the most affordable handguard options on the market. Though this depends on the model, there are many budget-friendly models that offer a similar degree of versatility as free float rails.
- These handguards are often much easier and quicker to install. There usually isn’t any modification needed to mount these handguards to your rifle. For some, you may need to remove the delta ring, but this is only for some models, not all.
- They can offer a similar degree of utility compared to free floating models. These handguards can come with M-LOK mounts, Key-Mod mounts, or even have picatinny quad-rails.
Cons
- Drop-in handguards don’t often hold zero as well as free-floating options. Unless a more secure mount is used, these handguards are held in by the delta ring’s spring tension, so accessories like lasers won’t hold zero as well under shock.
- The total length of these handguards is limited. Because of the mounts needed for drop-in handguards, their length is directly correlated, and limited, to however long that rifle’s gas system is.
- Lastly, heat dissipation on drop-in handguards isn’t as good as what most free-float models offer. Drop-in options have more direct contact with the barrel, and as such, they heat up quickly.
Popular Drop-In Handguard Manufacturers
Magpul: The MOE handguard from Magpul is one of the most well-known commercial drop-in handguards. It’s made of a durable polymer and was designed to be a direct upgrade from the standard A2 clamshell handguard. What makes a Magpul handguard so desirable is its low cost, durability, and its mounting capabilities. Priced around $45 or less, they are M-LOK compatible with several mounting points. In addition to the standard MOE handguard, they offer an MOE-SL model, which is slimmer and weighs less.
Bravo Company Manufacturing: The PMCR from BCM is another high-quality polymer drop-in handguard. Like the Magpul MOE handguard, this BCM handguard also has M-LOK mounting capabilities and incorporates an aluminum heatshield. Instead of smooth sides, it has added texturing for positive grip control. It’s another affordable option, commonly priced around $40.
Knight’s Armament Company: KAC was one of the first producers of high-quality aftermarket drop-in handguards. Their RAS (Rail-Attachment System) handguard provides mil-spec rifles with a secure mounting surface. With different lengths available, their handguards feature a quad-rail design that also comes with rail covers for added comfort. What separates the KAC RAS from other drop-in handguards is the way they mount. Instead, being held in by the delta ring’s spring tension, the RAS is clamped onto the rifle’s barrel nut, giving it much more security and the capability to hold zero.
Troy Industries: Like the RAS, the Enhanced Quad-Rail Handguard from Troy is a solid pick. Utilizing a patented clamping design, this Troy handguard mounts solidly onto the upper, allowing accessories to hold zero when mounted to the handguard. Integrated into the handguard are four QD points for slings, maximizing the utility and total accessory space.
Midwest Industries: Midwest Industries is a manufacturer of many high-quality parts and components for many different weapon platforms. While they produce their share of free-floating handguard options, their Gen 2 drop-in handguard is a popular pick for mil-spec rifles. This Midwest Industries Handguard comes with an M-LOK or a quad-rail configuration and is available in multiple lengths. Each model mounts to the standard mil-spec GI barrel nut and comes with integrated QD sling swivel points.
What is a Free-Floating Handguard?
Free-floating handguards are much different from drop-in models. Instead of requiring a delta ring and handguard cap, free-floating handguards attach directly to the barrel nut of the AR-15 and over the gas block entirely, requiring the use of low-profile gas blocks. Most commonly, these handguards are made from aluminum and come in varying sizes and shapes to complement different barrel lengths.
Being one of the most popular handguard options, free-floating handguards have become to the new standard on commercial AR-15s, offering more utility overall.
Pros
- Free-floating handguards have a very secure mounting method, and as such, hold zero much better than drop-in models.
- Free-floating handguards have less contact with the barrel, so while they can still get hot, they offer much better heat dissipation compared to drop-in options.
- The longer, uninterrupted length of these handguards offers more in terms of their mounting capabilities. There’s a lot of space to mount different accessories, allowing you to more effectively streamline the layout of your AR-15 rifle’s set up.
Cons
- Free-floating handguard options can at times be more expensive compared to drop-in handguard options. Granted, this depends on the materials, mounting system, and brand.
- While more of a nit-pick than a con, free-floating handguards can sometimes weigh more than drop-in models. That said, since free-floating options don’t need the bulkier barrel nuts and front sight posts of mil-spec AR-15s, the overall weight of the rifle is often lighter.
Popular Free-Floating Handguard Manufacturers
Geissele Automatics: Geissele is one of the premier manufacturers of aftermarket AR-15 components, with one of their most popular offerings being their handguards. They have multiple handguards which feature varying lengths, M-LOK compatibility, and even picatinny rail sections depending on the model. Of their handguards, the Super Modular MK4, MK8, and MK14 are some of the most popular. Each Geissele Handguard is similar but has a slight variation in the design, with the MK4 having picatinny on the front end of the handguard, while the MK8 and MK14 only have M-LOK rails aside from the upper picatinny rail.
Daniel Defense: Though best known for their firearms, Daniel Defense produces many accessories and components, including handguards. The most popular Daniel Defense handguards are the RIS II and RIS III. The RIS II is a free-float quad rail handguard that was designed for use on mil-spec AR-15s. In fact, it even won a contract with SOCOM in 2005. Instead of using a delta ring, the RIS II uses a replacement steel barrel nut and a bolt-up mounting system to free float the barrel. The RIS III is more akin to modern free-floating handguards. Utilizing the same bolt-up system as the RIS II. The RIS III, however, is a much lighter option that uses M-LOK instead of picatinny rails.
Aero Precision: Aero Precision offers multiple handguards, with their Enhanced and ATLAS S-ONE models being the most popular. The Enhanced handguard is available in multiple lengths and was designed specifically for use on Aero Precision’s Enhanced Upper Receiver. As such, this Aero Precision handguard uses a proprietary mounting system, making it incompatible with other uppers. Still, it’s a lightweight option that offers full length M-LOK compatibility.
Their ATLAS S-ONE handguard is compatible with all mil-spec pattern AR-15 uppers. Another lightweight solution, it too offers M-LOK support, however, it doesn’t have a continuous upper picatinny rail. Instead, the top of the handguard is rounded for a more comfortable grip, with the end of the rail having a picatinny section for front sights.
Expo Arms: If you’re looking for a utilitarian and simple handguard choice, Expo Arms handguards are some of the best offerings with their M-LOK handguards are some of their most popular options. Available in multiple lengths, and color options, they have full-length M-LOK slots on all sides, as well as an uninterrupted upper picatinny rail. Aside from these features, it’s one the most budget-friendly models in this list, with their standard models priced around or under $120.
If you’re in the market for a more premium option, their Enhanced Wedgelock handguard is the way to go. While functionally similar to their other handguard options, it features an incredibly durable locking mechanism. Its wedge lock design gives the handguard mount more surface area to grab onto the barrel nut, creating a rock-solid mounting surface. Like their standard model, this handguard is also available in multiple lengths and finishes.
SLR Rifleworks: SLR Rifleworks specializes in crafting top-tier handguards and parts for the AR-15. They offer multiple handguards, such as the Helix, Solo, and ION series. Each SLR handguard comes standard with QD sling points and full-length M-LOK on the sides and bottoms, though there are other models that can come with quad rails if preferred. The Helix and Ion both have continuous upper picatinny rails, while the Solo has an interrupted upper rail. In between the upper picatinny rails, there are M-LOK slots though, so you still have a place to mount accessories if desired.
SLR Rifleworks’ handguards are refined to be as light and durable as possible. In addition to this, each model mentioned is available in multiple sizes to complement varying AR barrel lengths.
Sons Of Liberty Gun Works: One of the most popular names in the firearms industry, Sons of Liberty Gun Works handguards are an excellent choice, making for a solid upgrade to your AR-15. They have an extensive lineup, with their M89 and L-89 Drivelock handguards being some of the most popular. The M89 Drivelock is an M-LOK handguard that uses their Drivelock attachment system, keeping it mounted securely against the barrel nut. Essentially, this mounting system locks the handguard to the barrel nut, providing you with a solid free floated barrel.
Their other handguard option, the L-89 uses the same Drivelock mounting system and is a direct upgrade to the M89. What separates these two handguards is the L-89’s use of a lighter titanium barrel nut and the two extra QD points at the rear of the handguard. Aside from this, it keeps the uninterrupted upper picatinny rail, as well as the full-length M-LOK slots on all sides except the top.
Which one should you get?
While both drop-in and free-floating handguards carry out a similar goal, choosing one over the other ultimately comes down to your preferences and how your rifle’s set up. If you have a mil-spec AR-15 with a delta ring and handguard cap, you don’t really have any other choice but to run a drop-in handguard. Drop-in handguards aren’t a bad option in any regard, but they don’t offer the same rock-solid support offered by free-floating models, unless they mount directly to the barrel nut.
Free-floating handguards are generally the better option. They provide you with a slimmer and more stable mounting surface that’s better for heat mitigation while offering much more real estate for accessories and optics. With drop-in handguards, you often only have enough space for key accessories like foregrips and a light, but with free floating ones, you can have space for much more. Though they are more expensive than some drop-in options, the added utility makes them more than worth considering for your next build.
Wrapping it Up
Choosing a handguard for your rifle is more than just a matter of personal preference, it can be a crucial decision that can alter your rifle’s functionality and maneuverability. Ultimately, the choice between a drop-in or free-float handguard comes down to how your AR-15’s upper receiver is configured.
If your rifle is setup in mil-spec or other configuration that requires a handguard cap, a drop-in handguard is your best bet unless you want to swap your gas block to a low profile one. If you’re considering making upgrades to your rifle, a quality free-floating handguard is one of the best places to start. That said, if your rifle already has a free-floating rail, swapping it out for a new one is easy.
Before you start buying the components needed to upgrade your rifle, it’s important to make sure you know how to install them. If you’re not experienced, assembling your AR-15 can be difficult, but our guide on assembling an AR-15 upper goes over everything you’ll need to know.
