A handguard is needed to protect your non-dominant hand from the heat coming from the barrel. During long-lasting shooting sessions, the barrel gets hot, and if not for handguards, it would be impossible to use a rifle for a long time.
Handguards also protect your weapon from damage and allow for the attachment of different mounting accessories like sights, foregrip, laser, lights, and other stuff.
Today, the market carries lots of AR-15 handguards of different types, lengths, and materials. So the question is how to choose a handguard that is right for you and your rifle? Let’s dig in.
Drop-in vs. Free-float Handguards
An AR-15 drop-in handguard is very easy to install. It can be done in a couple of minutes. The parts of the most drop-in handguards are fastened together by a cap in the front and secured by a delta ring in the rear. One more advantage is a broad price range. You can find cheap drop-ins, but be mindful of the quality of such products.
The disadvantage of such a system is that it contacts the barrel which can potentially affect accuracy.
AR-15 free-float handguards are booming today, gradually driving drop-in handguards from the market because they offer much more advantages. First of all, it doesn’t contact the barrel which results in higher accuracy. Also, they are lightweight and more robust due to their monolithic nature. Free float design is available in different lengths, and the longer the handguard, the more surface there is for attaching accessories.
Compared to a drop-in, a free-float handguard is more expensive and may require special tools for installation.
Picatinny vs. Keymod vs. M-LOK
Picatinny rail system is the standard in military and law enforcement. It features dovetail angles and grooves for mounting compatible accessories. This system is often used for a quad-rail handguard design where there are 4 rails placed on each side of a handguard. And while it is still preferred by many firearm owners, it’s losing its popularity because it's heavy and has sharp edges that can cut your hands or get caught in the clothes.
Keymod system has mounting slots resembling keyholes. To secure an accessory on a Keymod handguard, you need to insert the mounting lug into a slot and slide it to the narrower end. Thanks to such a design, the accessories are easier to align.
M-LOK system uses narrow, most often rectangular, slots. It offers great flexibility as you don’t need to position the mounting lug on a particular side of a slot like in Keymod. It means that you’ll have fewer issues when arranging all the accessories attached to your handguard. One more advantage is that the market of attachments that use the M-LOK system is greater than that of the Keymod.