The HDA3 Folding Stock

A joint product from A3 Industries and Haga Defense

It is not often that I get excited about a new stock hitting the market, but when I saw the HDA3 stock, I was enthusiastic to say the least. The HDA3 is a combined effort from Haga Defense and A3 Industries (formerly A3 Tactical). As a longtime fan of the Bushmaster ACR, the cosmetic resemblance of the HDA3 is one of the reasons I was so excited about it. That was until I got the HDA3 in my hands.

While I absolutely love the looks of the HDA3, I am even more impressed by just how incredibly well built this stock is. As an owner of other A3 stocks, I already knew they made great products so my expectations were high, but this thing legitimately blew me away.

Before I dive too deep into this, it is important to note that the version of the HDA3 that I got is the “Universal 1913” version. It will mount to any gun with a 1913 stock interface. Because of this universality, which I wanted specifically so I could try the stock on a number of different guns, it might look a bit odd on a couple of the guns I tried it on. If cosmetic appearance is important to you, which if we are being honest it is to all of us, fear not – they likely make a direct fit version for whatever gun you want to put it on. The list of direct fit firearms, for a product just hitting the market, is impressive.

I have several rifles with stocks that are similar in appearance. I have the F5 stock on a couple of Jakls, and I have another with a B&T stock on it. I like both of those stocks, but they do have their own drawbacks as well. The F5 has a reputation for being a bit flimsy and the adjustable cheek riser does not like to stay in the upper position. As for the B&T, I am not a fan of the length of pull adjustments because it requires two hands to operate.

The HDA3 is better than both of those two. It is extremely solid. No matter what you have the length of pull set to, there is no discernible wiggle to it. That is likely due to the extruded aluminum frame that lies at the heart of the stock. The length of pull adjustment is easily accomplished with one hand, and the controls for that are metal on metal, so they are much more solid than stocks with polymer controls. The cheek riser has 3 different height settings, which are selected but depressing the button on the right side. Like the rest of the stock, the cheek riser is extremely solid.

The only negative I can find with the HDA3 when compared to other stocks of similar design is the weight, and this is a minor negative at that. The HDA3 weighs a whopping 2 ounces more than the F5. Unless you are one of those people who measures the weight of their gun in grams, you won’t notice the weight difference, but you will absolutely notice the superior build quality.

If you are thus far diggin’ on the HDA3 like I am, but you don’t want to Form 1 your pistol, don’t fret. They sell the HDA3 in two different versions – as a stock and as a brace. The brace version uses your choice of buffer tube brace end like the Gear Head Works Tailhook or A3’s own Steady-Brace.

At $350, the HDA3 is not cheap, but you absolutely get what you pay for, and you are not locked in to one gun only. If you buy it for a gun that you later get rid of, but you want to keep the stock, A3 has you covered. While not currently available, they plan to sell the HDA3 model specific adapters separately allowing you to swap your stock (or brace) over to a new adapter for use on a different gun.

Along the same lines for those considering the brace version of the HDA3, it will be upgradeable to a stock with the purchase of a single part. Again, this option is not available yet but will be before too long.

The HDA3 stock can be purchased directly from either A3 Industries or Haga Defense, or from one of their authorized retailers. Currently it is only available in black, but FDE, OD green and gray will be available in the future.

The HDA3 is such a high quality piece of furniture, I am expecting to see it appearing as a factory option on firearms at some point in the future.