If you recall, back in 2020, Imperial Arms Co. had come out with their Cypher and Cypher X SCAR receivers. Well, they have continued to build upgrades for the SCAR platform. They now have an M-LOK CypherX receiver. On top of that, they have a billet lower that takes AR-10 mags and more importantly AR trigger groups! They have also made their own B&T stock/brace adapter. Let’s take a closer look at these SCAR17S upgrades.

SCAR 17S and Imperial Arms Co @TFB:

• TFB Review: How To Build A Pistol SCAR17Shorty With Imperial Arms Co’s CYPHER X
• CYPHER Virgin SCAR Receivers By Imperial Arms
• Review: Upgrading The SCAR17S With KDG

Slot Your SCAR17S With The M-LOK CYPHERX

When I built the CypherX the first time, I did ask Imperial Arms Co why they didn’t slot the receiver with M-LOK slots. They said they were working on it. Below is the evolution of the M-LOK CypherX. First is my original SCAR 17S FN Herstal receiver. Just above that is the Cypher X receiver which is an almost exact replica of the FN SCAR receiver. And finally above that is the M-LOK CypherX.

There are some considerable changes to the M-LOK CypherX receiver over Imperial Arms Co’s previous CypherX receiver.  Besides the obvious M-LOK slots on the sides of the receiver, the holes for the barrel screws are different. In fact, Imperial Arms Co ditches the black plastic thingies entirely for direct threading of bolts to the receiver to hold the barrel in place.

To install the barrel you simply insert it up into the receiver.

If you recall my article about building a SCAR 17S pistol with a CypherX, the receiver had a pin inserted into it to act as a denial device to prevent the CypherX from being able to use a full auto bolt. Well, the M-LOK CypherX has the protrusion machined now out of the receiver.

The build is relatively straightforward. Swap the barrel and bolt it in. Then bolt the rail and brass deflector. Finally, attach the rear end plate and you can reinstall the bolt and lower receiver.

SCAR17 Billet Lower

Billet lowers for the SCAR 17S are not anything new. A number of companies have made them and offered versions that can take AR-10/SR-25 magazines. When it comes to triggers for the SCAR17, there are only a handful of aftermarket options. I use a Geissele trigger while others like Timney or Shooting Sight. What sets the Imperial Arms Co billet SCAR17S lower receiver apart from the rest of the herd is its ability to use AR trigger groups.

The billet lower comes with the bolt catch which is held in place with a threaded pin.

Now you just install an AR trigger of your choosing along with an AR safety selector and pistol grip.

You can use any AR trigger you want, even binary triggers. I tried a binary in the lower and it worked but not as quickly as I had hoped. Also, the magazine popped out on the last round. I replaced the trigger after this and it ran fine.

Brace Yourself With The Imperial Arms Co Adapter

Stock/brace adapters are also not new but Imperial Arms Co puts their own spin on it. Most of the stock adapters, like the KDG ACR adapter or the picatinny adapter I used for my SCAR17S pistol build are made of aluminum. There have been assumptions made about metal adapters having an effect on the endplate causing the rear screws to cant. So Imperial Arms Co. molded their adapter out of polymer. Similar to the factory Ugg boot stock from FN America. They patterned their adapter to work with B&T-style stocks. This is great since SB Tactical designs some of their folding braces to utilize the same hinge and locking mechanism.

Installation is straightforward. You simply remove the hinge bolt, slide in the B&T style stock or brace of your choosing and reinstall the bolt. Then you install the adapter in place like the SCAR stock.

 

Final Thoughts On The M-LOK CypherX And Other Upgrades

The M-LOK CypherX is a great upgrade and should have been made from the start. The only other M-LOK receiver was made by Otto Arms however that project does not seem to have gone anywhere other than a one-off prototype. The M-LOK CypherX is not listed on their website just yet but I suspect it will be similarly priced to their CypherX which sells for $449.95.

I think the billet lower is a huge step forward and frees SCAR17S and SCAR20S owners to use common SR-25 magazines but more importantly, you can use AR triggers. So now you can use any trigger you like. The lower is $449.95 for black or $474.99 for FDE

The UMP/B&T stock/brace adapter is also another great option allowing you to use UMP or SB tactical folding braces. You can use any brace that works with the UMP hinge like their SBT brace or their new SBTEVO-G2 brace. The adapter sells for $89.99

For more information go to their website.