TFB Review: Strike Industries Dual Folding Adapter (Stock/Brace)

Nicholas C
by Nicholas C

At the last SHOT Show, back in January, Strike Industries unveiled a lot of new products. One of which was this Dual Folding Adapter. I was intrigued by it and its potential for a variety of weapons. Strike Industries sent one in for review so let’s take a closer look at it.

Strike Industries @ TFB:

The Dual Folding Adapter Swings Both Ways

The Dual Folding Adapter is a unique folding stock or brace. I will get into the stock/brace aspect in a bit but the main feature is that it can swing left or right. This is achieved by the M1913 adapter. It has dual buttons that you need to press to unlock one or both sides of the Dual Folding Adapter. If you press both buttons your stock or brace can be quickly detached by simply pulling it out.

To reinstall the stock or brace, you simply line up the leading end and shove it into the M1913 Dual Folding Adapter. See the two circular protrusions on top? Those are pressed in by the ramped surface on the Dual Folding Adapter.

When installed, you press one of the buttons on the adapter which presses directly on this steel pin. The pin has a cut in it and that is what catches on the adapter. So by pressing down, it unlatches and allows you to fold the stock or brace to the opposite direction. Press the right button, now the right side is free and you can swing to the left. Press the left button and it will allow the Dual Folding Adapter to swing to the right.

The adapter uses two screws to lock onto a rear Picatinny rail of a firearm.

Strike Industries includes a set of rubber shims that you can install into the recess of the Dual Folding Adapter.

I noticed a little bit of play so I installed the 1.3mm shims.

It helps but I might change to the thicker ones.

Stock Or Brace? Choose Your Own Adventure!

Strike Industries does not discriminate. They let you choose the purpose of your Dual Folding Adapter. You are adults, you can make your own decisions and choose your own adventure in your life. They include both a brace end cap and a stock end cap with a rubber butt pad.

The brace lacks a strap but looks like it potentially has slots for a strap, however, they are closed off. At the back of the brace is a QD hole for a sling swivel. While the stock butt pad has QD holes on both sides as well as the rear. There is a Torx screw inside the rear QD hole that holds the butt pad or stabilizer. Unscrew it to swap the end caps.

Strike Industries also sent in their adjustable cheek rest for the Dual Folding Adapter. There are two holes drilled through the stabilizing bar. These mate up with the screws for the cheek rest. You do not need tools to change the cheek rest position. There are three holes for the front and back. Which gives you plenty of adjustment to raise and lower your cheek rest. You can even stagger the height of the cheek rest if you so desire. There are seven different positions you can choose from. You cannot go to the extreme and use the lowest hole and highest hole of the cheek rest.

If It Fits, It Sits.

Here are a number of firearms that I tested the Dual Folding Adapter functionality on. Some of them have some unique quirks about them that make them not as well suited but still functional.

First up is my Pork Sword pistol.

The Dual Folding Adapter can swing to the right but the bolt handle gets in the way. I found that if I lift the bolt handle up before folding the brace, I can then lower the bolt handle on top of the stabilizing arm.

I tried the Dual Folding Adapter on my 10/22 Charger Enoch Industries Odin Chassis since it has Picatinny at the back of the chassis. The QD sockets prevent the stabilizing arms from folding all the way and locking in place. Normally the arm will drop down and lock into place. But if it cannot fold all the way, it won’t lock. Once locked, you simply pull up on the arm and swing the brace or stock out.

Just like the 10/22 Charger, I put the SI Dual Folding Adapter on the back of my H&K .22LR MP5 pistol. Due to the width of the end cap, the folding adapter cannot fold all the way.

The brace fits fine on shorter guns but what about full-length rifles? I swapped to the butt pad and installed the Dual Folding Adapter onto my Daewoo DR200. I am using a Stormwerks Picatinny adapter.

Rifles and pistols are all well and good. What about other weapons? Got you covered. Here is the Dual Folding Adapter on my LMT launcher. I used a Strike Industries Picatinny adapter on the end of the stock adapter.

One gun I was particularly interested in using the Dual Folding Adapter on is my SBR H&K SP5K-PDW. I have a unique need for a left-side folding stock as right-hand folding stocks cannot fit in the briefcase. I have been using a SIG Sauer MCX adjustable folding stock but I was curious how well the Strike Industries would work. It does and doesn’t at the same time.

One of the issues I have is finding a folding stock thin enough so the lid of my H&K briefcase can close. Well, since the Dual Folding Adapter can swing to the left, it fits in the case but it sits so far out that I cannot close the lid.

The Dual Folding Adapter sticks out like a sore thumb in the briefcase

Another minor issue is clearance for the release tab of the STANAG mount that holds the SP5K-PDW in the case. It sort of clears the stock but just barely.

Thankfully, the Dual Folding Adapter can be quickly detached before installing the gun into the case and I can store the stock in the bottom of the case.

Dual Folding Adapter Cross Compatibility

After trying out the Dual Folding Adapter, I noticed the stabilizing bar looks dimensionally similar to the SB Tactical FSB1913 brace. So I tried swapping it over and it works.

There is a big difference in the FSB1913 stabilizing bar. It is tapered. This is a carryover from the way SIG Sauer designed their stocks and braces and how they interface with their proprietary folding knuckle.

SB on the left, SI on the right.

What is more interesting is that the Strike Industries cheek rest also fits the SB Tactical FSB1913 stabilizing arm. There are no screw holes for the screws so they just go through the larger holes. The cheek rest will slide a bit but if you tighten the thumb screws down, it will grab and help keep the cheek rest in place. Ideally, someone can design and 3D print two simple plugs that fit in the gaps of the brace arm and then the SI cheek rest will have actual screw holes to attach to.

I also have a stock from Parker Mountain Machine but it required some modification to fit the Dual Folding Adapter.

Compatibility Concerns

Earlier I mentioned some minor issues with some specific setups I had with the Dual Folding Adapter. The 10/22 chassis and MP5 end cap had slight issues but nothing critical. That is not the case with running the Dual Folding Adapter on a SIG Rattler. At the range, I swapped the brace on my friend Kythe’s Rattler to see how well the SI brace would look and function.

It looks good but I immediately noticed a problem. The cheek rest blocks the charging handle from fully traveling rearward.

A minor inconvenience. I can lower the cheek rest and/or move the dual folding adapter down one Picatinny slot. Or I can remove the cheek rest altogether. However, the biggest issue I had was how wide the Dual Folding Adapter actually is. The charging handle on my friend’s Rattler is factory and it is just barely wider than the folding adapter. Also, the release buttons are a slight snagging point as they sit ever so slightly higher than the adapter so the bottom corner of the charging handle can hit them. If you pull up slightly as you pull the charging handle back, this is not a problem. Maybe you can get a wider charging handle for the Rattler but the adapter is really wide.

Final Thoughts On The Dual Folding Adapter

The Strike Industries Dual Folding Adapter is a unique folding stock or brace. It can swing left or right and it is up to you. You can quickly detach it if you need to. The stabilizing bar has a bit of wiggle and I am concerned over time this will increase. The latches are steel but the actual adapter they lock into is aluminum. I fear over time the steel will wear down the aluminum increasing the wiggle.

SI shows photos of their Dual Folding Adapter installed on what looks like a Brownell’s BRN 180. If you noticed by now the stabilizing arm is tilted down when it folds to the side. This is so it can clear the ejection port of your firearm.

You need to be thoughtful of what firearms you put this on. The SIG Rattler is similar to an AR design, especially with the charging handle so putting this on a similar firearm will have the same issues. Side-charging firearms seem better suited. The length of pull is a bit short, especially for the stock version so take that into consideration. SI does not have any length of pull adapters at this time. I would like to see Strike Industries offer the Picatinny mount separately so I can put it on multiple guns and just hot-swap the brace or stock when I use those firearms. I rarely need to shoot multiple guns at the same time.

The Dual Folding Adapter retails for $219.99 on the Strike Industries’ website. For more information check out their website.

Nicholas C
Nicholas C

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