Rock River Arms LAR-BT3 X-1 .308 Win 18″ Rifle 20rd

Description

The Rock River Arms LAR-BT3 X-1 .308 Win 18″ Rifle 20rd is a billet-set AR-platform rifle built for accurate, optic-ready performance right out of the box. Chambered in .308 Winchester, this semi-automatic rifle ships with an 18″ fluted, cryogenically treated stainless steel barrel and a free-float 17″ aluminum M-LOK handguard. It features a two-stage match trigger and an RRA Operator six-position carbine stock, making it a solid choice for precision shooting and hunting.

Specifications

Manufacturer	Rock River Arms (per manufacturer specs)
Model	LAR-BT3 X-1
Material	Billet 7075-T6 aluminum upper and lower receiver; stainless steel barrel
Compatibility	Accepts standard .308/7.62 NATO AR magazines, including the included 20-round magazine
Finish	Hard-coat anodized black (receivers); matte stainless (barrel)
Weight	Approximately 8.5 lbs (unloaded, per manufacturer specs)
Condition	New

Key Features

• 18″ Fluted, Cryogenically Treated Barrel — WHY IT MATTERS: The cryogenic treatment relieves internal stresses in the stainless steel, improving consistency and accuracy over standard barrels, while the fluting reduces weight and aids cooling during extended strings of fire.
• Two-Stage Match Trigger — WHY IT MATTERS: A crisp, clean break with minimal overtravel allows you to make precise shots without disturbing your sight picture, a must for long-range work or competition.
• Free-Float 17″ M-LOK Handguard — WHY IT MATTERS: The free-float design keeps barrel harmonics consistent by eliminating contact with the handguard, which directly improves accuracy. The M-LOK slots let you mount lights, lasers, or bipods without adding bulk.
• RRA Operator Six-Position Carbine Stock — WHY IT MATTERS: Adjustable length of pull lets you fit the rifle to your body or shooting position, whether you’re wearing heavy clothing or shooting prone, enhancing comfort and control.
• Billet Upper and Lower Receiver Set — WHY IT MATTERS: Machined from solid 7075-T6 aluminum, billet receivers offer tighter tolerances and a more rigid platform than forged parts, contributing to better accuracy and a premium fit and finish.

Who It’s For

This rifle is built for the traditional shooter who values accuracy and reliability over gimmicks. It suits precision rifle enthusiasts, hunters targeting medium to large game, and competitive shooters in matches like PRS or tactical rifle divisions. If you appreciate a hand-fitted, billet receiver with a match-grade barrel and trigger, this is your rifle.

Pros and Cons

Pros	Cons
Cryogenically treated barrel for enhanced accuracy and longevity	Heavier than some polymer-lower .308 ARs (8.5 lbs unloaded)
Two-stage match trigger eliminates the need for aftermarket upgrades	No iron sights included; optic required
M-LOK handguard offers modern accessory mounting without added weight	Price point ($1,826) puts it above entry-level .308 ARs

Comparison: Rock River Arms LAR-BT3 X-1 vs. Geissele Super Duty .308 vs. Daniel Defense DD5V1

Feature	Rock River Arms LAR-BT3 X-1	Geissele Super Duty .308	Daniel Defense DD5V1
Barrel Length	18″ fluted, cryo-treated stainless	16″ chrome-lined	18″ chrome-moly, nitrided
Trigger	Two-stage match (RRA)	Geissele SSA-E two-stage	Geissele two-stage
Receiver Material	Billet 7075-T6 aluminum	Forged 7075-T6 aluminum	Forged 7075-T6 aluminum
Weight (unloaded)	~8.5 lbs	~7.9 lbs	~9.2 lbs
MSRP	$1,826	$2,200	$2,399

The Rock River Arms LAR-BT3 X-1 offers a billet receiver and cryo-treated barrel at a lower price than the Geissele or Daniel Defense, making it a strong value for shooters who want precision without paying for a brand name premium.

FAQ

Does this rifle come with iron sights?

No, the LAR-BT3 X-1 does not include iron sights. It is designed for use with an optic, and the M-LOK handguard and flat-top receiver allow easy mounting of your preferred red dot, LPVO, or scope.

Is the barrel threaded for a suppressor?

Per manufacturer specs, the barrel is not listed as threaded. The muzzle is unthreaded, so you will need a gunsmith to add threading or use a clamp-on adapter if you plan to suppress it.

What magazines are compatible with this rifle?

The rifle ships with a 20-round detachable magazine. It accepts standard .308/7.62 NATO AR-pattern magazines from brands like Magpul, Lancer, and others. We recommend using quality metal or polymer magazines for reliable feeding.

How accurate is this rifle out of the box?

Rock River Arms claims sub-MOA accuracy with match-grade ammunition. The cryogenically treated barrel and two-stage match trigger contribute to consistent, tight groups. Expect 0.75–1.0 MOA with quality factory loads.

Can I use 7.62 NATO ammunition in this .308 Winchester rifle?

Yes, the chamber is compatible with both .308 Winchester and 7.62 NATO ammunition. However, for best accuracy, stick to .308 Win ammunition, as 7.62 NATO often has slightly different pressure curves.

Why Buy From Us

• ✓ Nationwide delivery (all 50 states) — we ship to your FFL dealer
• ✓ Ships 1-2 business days after payment clears
• ✓ 30-day return policy on unfired firearms (see our return page for details)
• ✓ Secure checkout with encrypted payment processing

Last updated: April 2026

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