Stern Defense RAB-AD: A Quick Detach Stock for AR-15 Rifles

The RAB-AD (Rapid Attach Buttstock Adapter) is an alternative to a side folding adaptor for AR-15 rifles. It allows the buttstock to be completely removed from the rifle, making it more compact for storage and transport. I have used side folding adaptors because they help reduce the length of an AR-15, but they can also make the gun too wide for some bags or cases. Another feature I like about an adaptor that completely removes the stock is the ability to interchange stocks if needed. If the buffer tube and spring are mil-spec, you can have multiple stocks with the RAB-AD attachment for interchangeability.

I first saw Stern Defense’s RAB-AD at TriggrCon and couldn’t wait to get my hands on one. It won the 2022 Golden Trigger Award for the most innovative accessory, and it’s not hard to see why. The adaptor has some advantages over traditional side folding stocks which we will get to shortly. But first, let’s talk about why you would need an adapter to begin with.

AR-15 rifles are great weapons for home defense and self-defense, especially now that pistol calibers have become commonplace. If you want a 9mm, .45, or some other pistol caliber, using one for self-defense has advantages over traditional handguns. Magazine capacity, lights, optics, and accuracy from longer barrels are just a few. The only issue, however, with an AR-15 pistol/rifle is their size. At home, this isn’t an issue, but if you want to keep one on you or in a vehicle, that’s a different story. Not everyone has room to keep a longer gun hidden in their car or bag.

Advantages of the RAB-AD Buttstock Adaptor

The first advantage of the RAB-AD is the ability to transport your rifle in a compact place. It literally takes seconds to connect the stock to the rifle. This works great for keeping the gun in a compact, hard case that doesn’t look like a rifle case. It also helps if the AR rifle/pistol is too long for the storage space in your car. As I have already mentioned above, the second advantage is the ability to swap out stocks.

Changing the stock on an AR isn’t hard, but I wouldn’t say it’s fast. If you have a few different stocks you like to use on your rifles, the RAB-AD system allows you to switch them around. One may be better for hunting, another for self-defense, and a third for range day or competition. The third advantage is that the RAB-AD system doesn’t use a removable plug, which is a downside to most folding stock adaptors.

I’ve had the plug fall out of my AR pistol before while carrying it in a bag. On side-folding stocks, the plug is the piece that connects the back of your BCG to the buffer spring, because of the extra space taken by the adaptor. The RAB-AD adaptor uses an extension that doesn’t fall out. You just connect and rotate the stock to lock it in place with the rifle. You can purchase the male assembly separately if you want to use multiple stocks with one rifle.

Installing the RAB-AD Adaptor

If you have installed a buffer tube on your AR-15 before, adding this adaptor is the same process, you’re just adding it in the middle of the receiver and buffer tube. For those who have not installed a buffer tube on an AR-15, don’t worry, it’s not hard. First, remove the spring and buffer from the buffer tube and then loosen the castle nut. An armorer’s wrench can be used for this, or an armorer’s wrench adaptor that comes with the kit and a 3/8 ratchet. Unscrew the castle, slowly letting pressure off the back plate.

The tube can be unscrewed from the back of the lower receiver. Keep your thumb over the buffer detent and spring as you unscrew the buffer tube. Take them out and put them up somewhere; you won’t need them for the rest of this project. Most AR-15s will have a detent spring sticking out of the back of the receiver. Just leave the spring where it is. Next, place the female camlock housing on the back of the receiver (pushing that detent spring back in).

Assembling

Screw the flange connector into the receiver, which holds the female camlock in place. Use the flanged connector tool to tighten it to about 20 foot-pounds. Now the male camlock housing can be placed on the buffer tube. With the back plate still on the tube, screw on the male camlock until it starts to get tight. Then back it up until it lines up with the back plate. Push the backplate against the male camlock and tighten the castle nut against them both (see photo below).

The buffer spring and buffer can be pushed back into the tube. There is a small lever sticking out that holds the buffer and spring in place. The buffer spring extension goes in after that. Now you can connect the stock to the gun by pushing the stock against the back of the gun and giving it a quarter turn. The stock will click in place and be ready to use. To remove it, push the button on the bottom of the RAB-AD and twist.

Final Thoughts

I have folding stock adaptors, and they work great. They serve a purpose when you need to make the gun shorter for storing in a backpack or other places. But sometimes the gun is too thick to fit in certain bags when the stock is folded against it. The RAB-AD lets the stock come off so you can place it in a different location or orient it differently. The biggest benefit for me, however, is the ability to easily switch out stocks with some of my other rifles.

I fired multiple mags through my rifle after the RAB-AD was installed and didn’t have any problems with it. For the price, this is a great product that can be added to just about any AR-15-style rifle. Stern Defense also offers a RAB-AD pic rail for those guns that do not use a buffer tube system. The adaptor simply attaches to the Picatinny rail on the back of the gun. If you like folding stock adaptors, you should give the Stern Defense RAB-AD a try.

Stern Defense RAB-AD features

• Designed, machined, and assembled in the USA.
• 7075 aluminum body.
• Steel internal components.
• Hard coat anodized for maximum wear protection.
• Buffer retainer to keep the buffer weight in the tube while disassembled.
• Buffer spacer compatible with all standard-length AR-15 bolts.
• Weighs 3.5 ounces.
• Adds 1.2 inches to the length of the gun.