LWRC SIX8A5RCK16 SIX8 A5 6.8mm Rem SPC II 16.10″ 30+1 Flat Dark Earth Cerakote Adjustable Stock

Description

The LWRC SIX8A5RCK16 SIX8 A5 6.8mm Rem SPC II 16.10″ 30+1 Flat Dark Earth Cerakote Adjustable Stock is a purpose-built gas piston rifle that marries the best of the LWRCI Enhanced and SPR platforms. It is fully optimized for the 6.8×43mm SPC II cartridge, delivering reliable cycling and reduced fouling in a short-stroke gas piston system. The rifle comes standard with a 16.10-inch barrel, a 30+1 magazine capacity, and a Flat Dark Earth Cerakote finish that resists wear and corrosion. According to LWRCI specs, the two-position adjustable gas block allows the shooter to compensate for suppressor use without altering the rifle’s inherent reliability.

Manufacturer	LWRCI (LWRC International)
Model	SIX8A5RCK16 SIX8 A5
Material	7075-T6 aluminum upper and lower receivers, cold-hammer-forged barrel
Compatibility	6.8mm Rem SPC II (6.8×43mm) ammunition; accepts standard AR-15 trigger groups with proprietary upper
Finish	Flat Dark Earth Cerakote
Weight	7.9 lbs (unloaded, per manufacturer specs)
Condition	New

Key Features

• Short-Stroke Gas Piston System – This system reduces carbon fouling in the receiver and keeps the bolt carrier group cooler and cleaner than direct impingement, which means less cleaning and more reliable operation over long strings of fire.
• Two-Position Adjustable Gas Block – Allows you to tune the gas flow for suppressed or unsuppressed fire without swapping parts. The low-profile design keeps the handguard sleek and prevents snagging on gear.
• 12-Inch SPR-Style Modular Rail System – Provides ample real estate for accessories like lights, lasers, and foregrips. The rail is free-floated for better accuracy and has M-LOK slots for direct attachment.
• Proprietary Upper and Lower Receivers – The enlarged ejection port is specifically contoured to clear the 6.8mm SPC II case heads without hang-ups, reducing the risk of stovepipe malfunctions during rapid fire.
• Flat Dark Earth Cerakote Finish – This baked-on ceramic coating offers superior scratch and corrosion resistance compared to standard anodizing, and the FDE color blends well with arid environments.

Who It’s For

The SIX8 A5 is built for the shooter who values reliability over raw speed. It suits hunters who want a flat-shooting, hard-hitting cartridge in a lightweight package, as well as law enforcement or home-defense users who need a suppressed-capable rifle that runs without hiccups. Traditionalists who appreciate a well-made, hand-assembled firearm will feel at home with this rifle.

Pros & Cons

• Pro: The piston system keeps the action clean and reduces the need for frequent lubrication – a real advantage in dusty or humid conditions.
• Pro: The adjustable gas block is simple to operate with a standard Allen wrench and does not require disassembly to change settings.
• Con: The rifle is heavier than a comparable direct-impingement AR-15 (7.9 lbs unloaded), which may be noticeable during all-day hunts or long patrol shifts.

Comparison

Feature	LWRC SIX8A5RCK16	Geissele Super Duty	Zev Technologies OZ9
Operating System	Short-stroke gas piston	Direct impingement	Direct impingement
Caliber	6.8mm Rem SPC II	5.56 NATO	9mm (pistol-caliber carbine)
Barrel Length	16.10″	16″	16″
Weight (unloaded)	7.9 lbs	7.3 lbs	6.8 lbs
Gas Block Adjustment	Two-position (suppressed/unsuppressed)	Fixed	Fixed
Finish	Flat Dark Earth Cerakote	Black anodized	Black anodized
Price	$2,946.00	$2,100.00 (approx.)	$1,800.00 (approx.)

The LWRC SIX8A5RCK16 offers a unique combination of piston reliability, suppressor-ready adjustability, and the potent 6.8mm SPC II cartridge, which the Geissele and Zev options lack. It costs more, but the build quality and feature set justify the premium for serious users.

FAQ

What ammunition types are safe to use in this rifle?

This rifle is chambered for 6.8mm Rem SPC II (6.8×43mm). Only use factory-loaded ammunition that meets SAAMI specifications for this cartridge. Do not use 5.56 NATO or .223 Remington. The barrel is rated for pressures up to 55,000 psi as per LWRCI specs.

Can I install a standard AR-15 trigger group?

Yes, the SIX8 A5 uses standard AR-15 fire control groups. However, the upper receiver is proprietary, so the bolt carrier group must be the LWRCI-specific 6.8mm unit. Drop-in triggers from Timney or Geissele will work without modification.

How do I adjust the gas block for a suppressor?

The gas block has two positions: suppressed (marked “S”) and unsuppressed (marked “U”). Use a 3/32-inch Allen wrench to rotate the set screw. Per LWRCI instructions, always start in the unsuppressed position and test fire before switching.

Is the barrel threaded for a muzzle device?

Yes, the barrel is threaded 5/8×24 TPI, which is standard for .30-caliber muzzle devices. It comes with a low-profile flash hider installed. You can swap it for a suppressor mount or compensator of your choice.

Does the 30-round magazine work with all 6.8mm SPC II ammunition?

Yes, the included 30-round magazine is specifically designed for the 6.8mm SPC II cartridge and has anti-tilt followers for reliable feeding. It is compatible with all factory 6.8mm loads that meet OAL specs.

Trust & Service

• ✔️ Nationwide delivery (all 50 states)
• ✔️ Ships 1-2 business days
• ✔️ 30-day returns
• ✔️ Secure checkout

Last updated: April 2026

Browse more in our AR Rifles or 6.8mm Ammo and AR Parts categories.