Sylvan Arms Gen3 Hinged AR-15 Folding Stock Adapter

    Sylvan Arms Gen 3 AR Hinge Folding Stock 1Adapter (2)

    Sylvan Arms has announced the release of the third generation of their AR-15 hinged folding stock adapters. As stated by the company, the main differences of Gen3 adapter from the previous generation are the lowered hinge and stronger, more durable design. Let’s take a closer look.

    Sylvan Arms Gen 3 AR Hinge Folding Stock Adapter (2)

    Sylvan Arms hinged folding stock adapter allows you to fold the stock on your AR pattern rifle for ease of storage and carrying the weapon. For folding the stock, you need to press the button on the side of the adapter and to unfold it, you simply need to flip it back because it is not locked in the folded position. As the warning on the adapter says, you can’t fire the rifle with the stock folded because, as you know, the recoil spring system in AR-15 rifles is inside the receiver extension and the BCG also reciprocates inside the buffer tube. So right before shooting, you’ll need to unfold the stock.

    I wonder if it is possible to design such adapters with a built-in mechanism that will prevent accidentally firing the gun when the stock is folded or not completely unfolded … maybe the hinging part could also pull the BCG out of battery? What do you guys think?

    The Sylvan Arms hinged folding stock adapter is CNC machined out of 7075 aluminum and has a black hard coat anodized finish. It is compatible with standard AR-15/AR-10 pattern receivers and buffer tubes with a 1-3/16”x16 thread pitch.

    In order to install it, you’ll first need to screw the adapter into the AR-15 receiver and fix it in place by the provided castle nut. Then, you’ll need to screw the buffer tube into the hinging section of the adapter and fix it in place via a standard castle nut. The hinging part has a built-in buffer retaining pin to capture the buffer and recoil spring when the stock is folded. There is also a QD sling swivel socket at the rear portion of the adapter.

    Sylvan Arms Gen 3 AR Hinge Folding Stock Adapter (13)

    As you can see in the above-embedded image, the adapter creates a gap between the bolt carrier and the buffer due to its 1.3″ length. To compensate for this gap, the adapter comes with a bolt extension piston (see below) that is inserted into the bolt carrier tail to bridge that gap. Now, the downside is that you’ll end up with a longer stock/buffer tube. Well, that’s the tradeoff for having a folding stock on your AR and I don’t think it is a huge issue if you use an adjustable stock.

    The weight of the adapter is 6oz and the bolt extension weighs 2.2 oz. That 2.2 oz is added to the mass of your BCG – something to consider if you are tuning the system to work with a specific load or parts combination.

    Sylvan Arms Gen 3 AR Hinge Folding Stock Adapter (11)

    The Sylvan Arms Gen3 AR Hinge Folding Stock Adapter is listed on the company’s website at an MSRP of $179.99.

    Sylvan Arms Gen 3 AR Hinge Folding Stock Adapter (14)

    Sylvan Arms Gen 3 AR Hinge Folding Stock Adapter (4)

    Sylvan Arms Gen 3 AR Hinge Folding Stock Adapter (3)

    Does anyone of our readers have experience with the Sylvan Arms side folding adapters? If so, please tell us in the comments section what do you think about these gadgets.

    Images from

    Hrachya H

    Being a lifelong firearms enthusiast, Hrachya always enjoys studying design, technology and history of guns and ammunition. His knowledge of Russian allows him to translate and make Russian/Soviet/Combloc small arms related information available for the English speaking audience. Hrachya also writes for
    Should you need to contact him, feel free to shoot him a message at [email protected]