FN SCAR | F5-ACR Gen 3 Cyberarm Light Brace + Stock Combo

FN SCAR Folding Stock & Brace Combo — F5-ACR Gen 3 Complete System

Cyberarm Light Brace + F5-ACR Gen 3 Stock + Gen 3 Chassis

The FN SCAR was built bufferless from the ground up, with its recoil system housed entirely in the upper receiver. That’s what makes it such a good host for the F5-ACR Gen 3 Chassis. The chassis bolts directly to the SCAR’s rear stock interface — no buffer tube, no adapter block — and keeps the platform’s fire-while-folded capability intact while pulling weight off the tail of the gun.

This combo ships with both rear-end options. The Cyberarm Light Brace weighs 95.75 grams, roughly half the 179.50-gram standard version, and is the shortest, lightest way to run a pistol-configured SCAR. The F5-ACR Gen 3 Stock is what you install once your SBR paperwork comes back. Buying them together means you’re not hunting for a back-ordered stock the week your approval lands.

Every chassis is CNC-machined in-house from solid 6061 billet. The skeletonized profile comes out of material-optimized modeling — metal is removed only where the load path allows it, so the finished part stays among the most rigid components on the rifle. On 7.62 builds that rigidity is the whole point: no flex, no rattle under recoil, and a zero return that’s repeatable through the fold cycle.

Topside, the Gen 3 carries a tool-less adjustable cheek riser. Given the SCAR’s high rail line and the tall optic mounts most people run on it, that adjustment range solves a real ergonomic problem instead of padding a spec sheet. The side-folding mechanism locks up positively in both positions.

Key Features

• Both rear-end configurations in one purchase — Cyberarm Light Brace and F5-ACR Gen 3 Stock
• 95.75-gram Cyberarm Light Brace — about half the weight of the standard version
• Direct fit to the FN SCAR rear stock interface — no buffer tube, no adapter hardware
• Tool-less adjustable cheek riser for optic and head-position alignment
• Side-folding with positive lockup; preserves fire-while-folded
• CNC-machined 6061 billet with load-path skeletonization
• Fits 5.56 NATO, .300 BLK, and 7.62×51 NATO/.308 Win SCAR variants
• Made in the USA

Why It Matters on a SCAR

The SCAR’s factory stock is capable but heavy, and rear-biased mass is the first thing most owners want to fix. The Gen 3 Chassis removes that weight without giving up folding function or lockup rigidity — a meaningful upgrade on short-barreled and PDW-style builds where every ounce behind the receiver works against you.

The combo adds a second reason: timing. A Form 1 approval can take months, and there’s no sense leaving a rifle in a drawer or buying the stock twice. Run the brace through the wait, swap to the Gen 3 Stock when the stamp arrives.

Building the Host Gun

This chassis fits both sides of the SCAR line — the 5.56/300 BLK guns and the 7.62 rifles — so the build path depends on what you’re after.

For compact pistol builds, the 7.5-inch SCAR 15P is the shortest way in. It ships at 5.65 lbs with a 19.75-inch overall length, and gets shorter still once the Cyberarm Light Brace is folded. Palmetto State Armory currently has both variants well under FN’s list:

• FN SCAR 15P — 5.56 NATO, 7.5″ barrel, 30rd, FDE — $1,999.99 (reg. $3,738.99). Chrome-lined barrel, three-prong flash hider, FDE anodized receiver, fully ambidextrous controls. Pair it with the FDE or OD Green chassis for a matched build.
• FN SCAR 15P — 300 Blackout, 7.5″ barrel, 30+1, Black — $1,999.99 (reg. $3,820.99). Modeled after the SCAR-SC PDW, with an adjustable low-flash gas regulator and a bolt carrier tuned for the pistol-length gas system. The natural choice for a suppressed subsonic setup, where trimming rearward weight matters most.

Either 15P is the strongest argument for the combo specifically — both are pistols out of the box, and both are prime Form 1 candidates.

For 7.62 builds, the FN SCAR 17S in 7.62x51mm NATO is where this chassis earns its keep. The factory 17S stock is a telescoping side-folder in composite polymer, and it’s the heaviest single thing hanging off the back of the gun — an 8-lb rifle carries a lot of that mass behind the receiver. Swapping to the F5-ACR Gen 3 Chassis pulls weight forward and stiffens the rear interface, which is exactly what a hard-recoiling .308 wants. Billet lockup doesn’t develop the play a polymer folder eventually does.

Every SCAR in the line runs FN’s short-stroke gas piston system with no buffer tube, so the chassis drops straight in across calibers with no adapter hardware.

Important Compliance Notice

This combo includes both a pistol stabilizing brace and a rifle stock. Installing the stock on a pistol-configured firearm may constitute the making of a short-barreled rifle under federal law. Verify that your configuration complies with all applicable federal, state, and local regulations before installation.

Specs table: