With the AR-15 being such a popular, easily upgradable, and highly customizable rifle you shouldn’t be surprised there are dozens of different stocks for it. It’s one of the few weapons I could sit and create an entire article on just the stock options you have. If you are looking to build your own rifle, the stock you choose will affect the weapon’s performance. The rifle stock is the part of the AR platform that connects you to the weapon. Choosing the proper stock for your weapon involves identifying its purpose and your own personal preferences.
Fixed stocks are what the original M16 and AR-15 rifles were built on. The standard A2 stock remains a favorite of NRA High Power shooters and even the United States Marine Corps. Why mess with success right? Fixed stocks are very strong and quite durable. They often have a longer overall length of pull and are made to be quite durable. I’ve used an A2 stock quite a bit during my early military days and have never seen one break, even when practicing butt strokes in martial arts training.
Fixed stocks are generally heavier than alternative options, and that isn’t always a bad thing. For a full sized, 18 to 20 inch barreled AR-15 a fixed stock can be advantageous. The longer the barrel, the more weight you have hanging off the end of your weapon. The heavier and more robust fixed stock will help balance that front forward weight, especially when adding accessories like bipods.
The fixed nature of these stocks also keeps them from wiggling. Almost all collapsible stocks have a little wiggle to them. Even just a little wiggle can be frustrating when using a magnified optic to hit a small target. Fixed stocks are certainly better for rifles that stress precision and accuracy. Also, for states that ban collapsing stocks under assault weapons bans (Looking at you California) a fixed stock may be your only option.
Fixed stocks aren’t limited to standard A2 stocks either. Magpul produces the PRS series of stocks, although some argue these aren’t fixed stocks entirely. They allow the user to extend the butt pad of the weapon, but for most purposes, they are fixed stocks. They also produce a Carbine MOE fixed stock, which is perfect for unfree states. It’s lighter and shorter and better suited for your standard 16-inch barrel rifles.
The Luth MBA series is another high-end option for a fixed stock, and companies like Battle Arms produce very lightweight fixed stock options for 3 Gun and other action shooting sports. Fixed stocks are making a bit of a comeback with competition shooters, retro builders, and the Special Purpose Rifle fad.
The downsides are obvious; you can’t adjust it. Smaller folks may have issues shooting rifles with fixed stocks, especially when utilizing tactical gear and plate carriers. They can make storing weapons and operate with them in and out of vehicles difficult.
Collapsible stocks are by far the most popular stock option for your basic M4gery. With carbine size rifles being the most common and popular choice, every AR-15 manufacturer I know of has the collapsing stock as the base option. On top of that, collapsible stocks are also the cheapest option for builders. There are tons of cheap crap Chinesium plastic ones available, but when I say affordable, I mean companies like Magpul. Collapsing stocks are what the U.S. Army is using almost exclusively, and what the Marine Corps is moving too.
Collapsible stocks are adjustable stocks with anywhere from 3 to 8 different positions. The most common stock and buffer tube combo allow 6 positions of adjustment. The benefits of a collapsing stock are namely the ability to customize the fit of the rifle to the shooter. The ability to customize the length of your rifle can be invaluable for smaller shooters, or when a shooter is utilizing body armor or other tactical gear. A smaller weapon is also an easier weapon to use in close quarters environments, and especially in and out of vehicles. A collapsing stock allows for easier storage and transportation of firearms.
A rifle equipped with a collapsing stock is well suited to be shared between different shooters. This is one of the primary reasons the military and most police forces are leaning towards the collapsing stock. It really allows a rifle to be adapted to a variety of shooters, both big and small. Collapsing stocks are generally lighter than fixed stocks, and balance both carbine and SBR rifles well.
Collapsible stocks are popular because of their simplicity and versatility. Collapsing stocks are basically the compromise between PDW stocks and fixed stocks. They most often offer an excellent cheek weld as well as solid shoulder to stock contact. Collapsing stocks offer the widest variety of stock options for shooters with every company under the sun producing collapsible stocks. This has led to some fascinating designs from BCM, Magpul, Mission First Tactical and more.
Collapsing stocks aren’t as stable as fixed stocks, but unless you are shooting extended distances or at small targets, this isn’t a major issue. Collapsing stocks are generally the best choice for your typical carbine length AR-15, especially for shooters looking for a home defense rifle.
PDW stocks are pretty new to the AR market but have become popular pretty fast. Troy produced one of the first commercially viable options for an AR PDW stock, and from there the numbers of PDW manufacturers exploded. A PDW stock is a new take on the collapsing stock design. PDW stocks are about as small and light as you could possibly go with a stock. They greatly resemble wire frame SMG stocks, and you really can’t go any smaller or lighter than a PDW stock.
PDW stocks are functional on carbines, but really excel when it comes to short barreled rifles. If you truly want to minimize the size and profile of a small rifle a PDW stock is the way to go. The small size of PDW stocks allows you to easily transport rifles in a discrete way if you choose. PDW stocks are often adjustable with a variety of different positions, and like regular collapsible stocks, there are usually 3 to 6 positions the stock can be adjusted too.
The PDW is perfect if you really have a need to shrink your AR-15 as much as possible. However, there are a few issues with PDW stocks. They are the least stable stocks and make obtaining proper cheek weld difficult and even painful. PDW stocks utilize specialized buffers and buffer assemblies, and many require proprietary bolt carrier groups. On top of that, these stocks tend to be the most expensive option, often costing several hundred dollars. Their unique appearance and utility make them a niche option, but one that can’t really be fulfilled by other stocks.
There isn’t necessarily a side folding AR stock, but there a few adapters available that allow you to convert your stock into a side folder. The most popular and robust option is the LAW side folding adapter. It’s the best built and was the first option to make a side folding AR-15 stock possible. To use this adapter you’ll need to use a collapsible stock or a pistol brace. The adapter fits between the lower receiver and the buffer assembly. The buffer tube connects to the adapter, and the adapter connects to the lower receiver.
The issue with folding an AR stock is the buffer assembly. It’s needed to fire the weapon, so with the stock and buffer assembly folded the weapon cannot be fired more than once. This is a minor complaint since without a stock the weapon isn’t exactly accurate. However, folks looking into the option should know the AR-15 is not designed to be fired with a folding stock. A folding stock allows you make a standard carbine quite compact, and easily hidden or stored. The LAW adapter, in particular, is a quick action device that takes less than a second to fold and unfold. With this quick action folding ability, it’s a great option for working in an out of vehicles, or for discreet rifle transportation.
These aren’t stocks, but I tossed them in because they attach to the end of a weapon and don’t require their own article. Pistol arm braces make firing AR-15 pistols much easier and provide a much more stable platform for firing the unwieldy AR-15 pistol. The ATF has gone back and forth on pistol braces quite a bit, approving them, and even proclaiming they can be shouldered without the pistol becoming a short barreled rifle. They then reversed their opinion stating shouldering a pistol arm brace constituted a redesign of an AR pistol and turned it into a short barreled rifle.
However, the ATF changed their opinion once more in early 2017 stating you could in fact shoulder an AR-15 pistol with an arm brace without creating a short barreled rifle. So as of this writing, you can shoulder a pistol arm brace without running afoul of the ATF. Pistol arm braces are quite dynamic and varied with fixed and PDW models widely available. They can also function with the LAW folding stock adapter. The majority of them simply friction fit over a pistol buffer tube.
They make shooting an AR pistol much, much easier. From shouldering it to using it as a cheek rest, it makes shooting an AR pistol accurately much easier. The addition of an arm brace also covers up that ugly and undesirable buffer tube that flaps out in the wind.
Regardless of the option you choose, go with a quality rifle stock. If the stock cost 5 bucks, there's a reason for it. With so many affordable options by companies like Magpul, there really isn’t a reason to go super cheap. A quality stock will take you far, and last a lifetime. Just be honest with yourself, and with the weapon you want to have.
- Magpul MOE Rifle Stock ($67)
- Magpul PRS GEN3 Precision-Adjustable Stock ($243)
- MFT Battlelink Minimalist Stock Mil Spec ($50)
- VLTOR IMOD Standard Stock ($95)
- MVB Industries PDW ARC Stock H1 Buffer 5 position ($433)
- Law Tactical Gen 3-M AR Folding Stock Adapter ($259)
- Maxim Defense CQB Pistol PDW Brace ($376)
* Items may have been out of stock or discontinued at the time of this writing.