There’s nothing wrong with an A2 stock. They’re simple, streamlined, and effective rifle stocks, but they do leave something to be desired when it comes to features.
Removing your A2 rifle stock and replacing it with a more modern fixed version such as the Magpul Fixed Carbine stock can provide sling attachment points and the ability to fine-tune the length using spacers. It’s also one of the easiest AR-15 upgrades you can install.
Alternatively, replacing it with an adjustable stock like the B5 SOPMOD offers even more adjustability as well as the option to upgrade your end plate to a QD version. Some adjustable AR-15 carbine stocks even allow the use of aftermarket accessories like cheek risers or monopods.
But before you can upgrade to something shiny and new, you’ll need to get your old A2 stock off.
What is an A2 stock?
An A2 rifle stock is simply a fixed rifle stock that matches the dimensions of the stock on the M16A2 military rifle. While AR-15s and M16s differ in many ways, they do share the same stock assemblies, allowing an AR-15 to use either a surplus A2 stock or a reproduction.
A2 stocks measure around 10.5″ long (depending on your buttplate and where you measure from) and create an overall length of pull of 13.5″, which is generally considered to be on the long side for an AR-15.
True A2 stocks feature a storage area accessed through the buttplate and have a simple, fixed sling loop located at the bottom rear of the stock. However, some modernized iterations add features like QD sling cups and adjustable cheek risers or length of pull.
Removing an A2 stock from an AR-15 is one of the easiest modifications you can do and one of the least tool-intensive. Unlike carbine stocks, there is no castle nut holding the buffer tube in place, so you can skip the castle nut wrench. At a minimum, you will need a screwdriver or Allen wrench, but not much else.
In most cases, an A2 stock will be secured to the buffer tube using a flat-head screw. However, versions with Phillips-head or Allen screws do exist, so double-check your stock before starting.
Additionally, we recommend using a lower receiver block for this operation. Mounting your lower receiver on a receiver block and vise will provide a much more stable platform and makes it easy to work and move freely around the receiver. It also keeps both of your hands free, since you won’t need to hold the receiver in place while turning screws or removing parts.
Removing the stock
As with any firearm maintenance or modification, start by clearing the firearm of all ammunition. Remove the magazine, set it aside, and check to make sure the chamber is clear.
Next, remove the upper receiver by pushing out the takedown pins from the left side of the rifle to the right. Once the receivers are separated, you can set the upper aside.
Since you’ll be working on the stock and buffer tube, remove the buffer and recoil spring next. Depress the buffer retainer pin with your thumb or a screwdriver and slide the buffer and attached spring out of the buffer tube. Since the parts are under spring pressure, they may shoot forward a bit once the buffer retainer pin is depressed.
Set the buffer and spring aside. Using your screwdriver or Allen wrench, loosen and remove the top screw in the buttplate of the stock, but don’t allow the stock to move away from the receiver yet. Unlike a carbine stock, A2 stocks don’t use an end plate, so the stock itself is the only thing holding in the rear takedown pin and spring.
With the upper screw removed, slowly back the A2 stock off of the buffer tube. We recommend keeping one hand cupped around the lower portion of the stock, near the receiver, in case the takedown pin spring slips free. Once the stock has moved back a few inches, the pressure will be relieved from the spring, and you can safely remove the stock.
After removing the stock, you’ll notice a small, round piece of plastic on the end of the buffer tube. This is the A2 spacer. It’s not attached to the buffer tube, so you can simply take it off and put it aside.
Next, remove the takedown pin spring and detent and set them aside. Unscrew the buffer tube from the receiver, taking care to keep a hand on the buffer tube retainer detent. As soon as the buffer tube is backed out far enough, it will try to shoot out, so it’s important to keep pressure on it. When the buffer tube is backed out far enough, remove the buffer retainer pin and spring, then finish unthreading the buffer tube.
When the buffer tube is removed from the receiver, your disassembly of the stock is complete.
Does changing the stock on a rifle affect accuracy?
Technically, no, changing the stock on your rifle will not improve or degrade its accuracy in any measurable way. However, that’s not the entire picture, because changing the stock can improve your ability to shoot accurately with your rifle.
The distinction here comes down to the difference between practical and mechanical accuracy. Mechanical accuracy, which is generally what we talk about when we discuss accuracy, is a measure of how accurate the rifle is when excluding all other factors.
Clamp a rifle in a vice and pull the trigger using a plunger, without a human directly touching it, and the resulting group will tell you the mechanical accuracy it’s capable of.
Practical accuracy, on the other hand, is usually a more relevant measure and takes into account the human variable. Practical accuracy is a measure of how accurate you (or in some cases, an average user) are capable of being with the platform.
While changing the stock won’t alter the mechanical accuracy of the rifle—you could even remove the stock entirely, and the mechanical accuracy will be unchanged—it can improve the practical accuracy.
A heavier stock can help soak up the energy from a shot and reduce felt recoil. A more secure or customizable cheek weld can create a more consistent head position. Some stocks even allow for the use of rear monopods, significantly improving stability.
There are myriad ways a better stock can improve your practical accuracy, many of which are dependent on the user. Not all marksmen have the same preferences, so what improves accuracy for you may degrade it for someone else.
Removing an A2 stock is a simple operation, one that’s perfect as a starting point for new armorers or AR-15 enthusiasts. But, now that the stock is off, you’re going to have to figure out how to get it or another stock back on if you want to be able to use your rifle.
To reinstall your A2 stock, simply follow the instructions in reverse. If you’d like to replace your A2 stock with a more modern stock, you can find instructions for installing a standard carbine buffer tube and stock in our article How to Assemble an AR-15 Lower.