Gear Review: Flux Defense Raider X Chassis

Recently, I wrote an article about the H&R Commando rifle in 300 BLK. It’s a very cool rifle that combines retro flair with modern conveniences. I saw the rifle as a kind of truck gun or ranch rifle…something to keep on hand as a “break-in-case-of-emergency” option.

That rifle and its setup won’t be ideal for everyone (what is?). And in the end, when fully equipped, I wouldn’t call it an inexpensive setup. People need to stay within their budgets after all.

So, instead of buying a new gun, let’s explore ways to upgrade a gun you may already own to make it more capable. That’s why I’m looking at chassis conversions for commonly owned pistols. The first article detailed the Recover Tactical S-PRO with a GLOCK 17 Gen 4 pistol. It surprised me and made me reconsider the GLOCK chassis. The latest example of these is one you’ve probably seen before: the FLUX Defense Raider X for the SIG SAUER P320.

Truck Gun?

Truck gun, ranch rifle, bedside companion…whatever you call it, they all serve similar purposes. The debate covers everything from pistols and shotguns to AR-15s, PCCs and PDW-style firearms. I use the term loosely to mean any gun that’s kept nearby, whether by the bed, in a vehicle, or in a side-by-side.

The best choice depends largely on your environment, from a rural farm to a suburban home or city apartment, and ultimately on your preference, training, and familiarity. Your setup—optics, lights, slings, ammo, and magazines—should be tested and customized to suit your needs.

Caveat: If you’re interested in pursuing this concept, be sure to check your local laws regarding the transport of guns in vehicles, particularly long guns and NFA items. Free states tend to favor handguns, but things can get spicy when long guns and other scary items are loaded in vehicles. Be sure to know what’s legal where you live.

A PDW for You

A PDW — personal defense weapon — checks many of the boxes for a portable lead dispenser. It’s handy and maneuverable. It’s easier to shoot accurately than a handgun. And it’s usually chambered in a caliber like 9mm, something that’s widely available, inexpensive to shoot and capable within a hundred yards or so.

Like the Recover Tactical chassis, you don’t need to buy an entirely new gun to have one of these. Several of today’s pistol designs use independent, modular “fire control units” that are serialized and separate from the pistol’s frame, giving users more flexibility. The SIG P320 (I won’t get into the controversy around them here) made this idea of modularity mainstream. As a result, several aftermarket companies have developed clever ways to transform the P320 into a PDW.

Flux Defense

I’m not sure if Flux Defense was the first company to do this, but they were the first I saw and thought, “I need that.” Yes, I was influenced by a YouTube video. Yes, sometimes influencer marketing works. Do I hate that it worked on me? Maybe, but this tricked-out PDW is awesome. After many range trips, I find that the Raider X is a well-designed chassis system that truly elevates the P320 pistol.

The Raider X is a compact PDW chassis designed to push your SIG P320 beyond conventional handgun limits. It combines the speed and maneuverability of a pistol with enhanced control, stability, and extended capacity, delivering increased firepower in a duty-ready, concealable platform.

The Spec Sheet

Having already owned a stock SIG SAUER P320, I researched and acquired the components and accessories needed to transform it into the ultimate PDW. Before I break it all down, here’s a list of everything:

• Flux Defense Raider X
• F10 Top Charging Handle
• Side Accessory Pic Rails
• P320 Threaded Barrel
• Herrington Arms HC320R Compensator
• 21-Round Magazine
• Holosun SCRS Dot
• QD Optic Mount
• Weapon Mounted Light (SIG FOXTROT2R)
• Edgar Sherman Designs Sling

The Build

The build is as simple as it gets. Make sure the P320 is unloaded, take out the magazine, rotate the takedown lever, remove the slide, and then detach the takedown lever from the frame. Next, the fire control unit will come out (you may need a flathead screwdriver to pry it out, especially if it’s your first time). Then, drop the FCU into the Raider, reinsert the takedown lever, and place the existing P320 slide on it.

Voila. After that, it’s all about customizing.

For optics, I chose the Holosun SCRS, mounted on an American Defense 509T QD mount. The optic is solid and one of the best for people with astigmatism. Then I replaced the factory P320 barrel with a threaded one and added a compensator from Herrington Arms. That helps reduce recoil and creates a more linear impulse. You could easily add a suppressor if you like, as well…dealer’s choice. Just make sure it fits within the Flux chassis.

To improve ergonomics, I added the Flux side pic rails, which also serve as a handy thumb rest and help with recoil management. Since the slide sits in the frame as it does, it can be difficult to manipulate. Fortunately, Flux designed the F10 charging handle. It replaces the front sight and makes slide manipulation much easier.

The final additions were a sling and a light. For the light, I chose a SIG FOXTROT2R which is reminiscent of a Streamlight TLR-7. For the sling, I added an Edgar Sherman Designs sling. These are fairly minimalist and simple to use.

How Does It Work?

In short, flawlessly. It was easy to sight in and even easier to shoot. The brace deploys with force via a lever on the side. The front spare magazine storage works just as well.

Unlike the Recover Tactical chassis, the mag release is easy to manipulate with either hand. For your support hand, apply half pressure to the front magazine release and the spare mag drops free. Apply full pressure, and both the empty and spare mags are released.

There is also a standard left-side mag release and an ambi safety, making operation of the Raider X P320 straightforward and intuitive. Even the pistol grip is ergonomic and features a flared magwell. Honestly, I don’t have anything bad to say about it.

It’s also a people pleaser. Every time I bring it out, everyone wants to shoot it. Whether they’re experienced shooters or novices, everyone enjoys it.

But what about using it as a truck gun? I think it fits the role perfectly. Since it’s classified as a pistol, it falls under the concealed weapons laws of many states. So here in Ohio, I can keep it hidden and loaded in my vehicle (as long as I follow the rules of where I can and can’t have it). While it might not be the best option for the wide-open spaces, it fulfills a variety of roles in urban and suburban environments really well.

Is It Worth It?

If you already own a SIG SAUER P320, then you’re halfway to owning a capable PDW—no additional FFL visits required. Just order the chassis online and have it shipped right to your home.

The Raider X P320 is priced at $419.99. You can get one in black, green, or FDE. What you’ll get is a compact, maneuverable package that offers greater effectiveness than a handgun.

The price is comparable to the Recover S-PRO chassis. However, there are more accessories and aftermarket support for the Raider, which will add to the overall price. Truthfully, this is one I recommend.