Rock River Arms LAR-BT3 Varmint — .308 Win, 20+1, 20" Stainless Bull Barrel, Black Billet Receivers, 17" M-LOK® Handguard, OEM NSP-2 Carbine Stock, Hogue® OverMolded Grip (Model XBT31521 | UPC 842834119752)

Engineered to print tiny groups on warm barrels and windy days, the Rock River Arms LAR-BT3 Varmint takes the proven .308 Winchester platform and optimizes it for stability, heat control, and repeatable accuracy. A 20-inch stainless bull barrel anchors the build, while billet-machined upper and lower receivers add rigidity that helps keep your zero locked, string after string. The long 17" free-float M-LOK® handguard gives you room for bipods, bags, and accessories without touching the barrel, and the rifle’s ergonomics are finished with an OEM NSP-2 carbine stock and a palm-filling Hogue® OverMolded beavertail grip for comfort and control.

Why the LAR-BT3 Varmint Dominates the Bench and the Back Forty

• 20" Stainless Bull Barrel: Heavy contour resists heat-induced POI shift, promoting tight, repeatable groups during extended shot strings. Stainless steel cleans easily and shrugs off the elements.

• Billet Receiver Precision: Billet upper/lower receivers enhance fit and alignment, supporting consistent harmonics between the barrel and handguard for long-term accuracy.

• 17" Free-Float M-LOK® Handguard: Plenty of real estate for bipods, Arca/M-LOK adapters, QD sling cups, and barricade stops—all while staying off the barrel to protect accuracy.

• Ranch-Ready Ergonomics: The NSP-2 carbine stock offers a stable, familiar cheek weld, and the Hogue® OverMolded grip delivers a cushioned, no-slip hold in hot, cold, or wet conditions.

• .308 Winchester Authority: Broad bullet selection (125–180gr+) for dialing the ideal varmint or medium-game load—and match ammo for ringing steel at distance.

Real-World Accuracy Advantages

• Thermal Stability: The bull barrel’s mass mitigates rapid heating, keeping your zero and vertical dispersion in check during high-volume varmint sessions.

• Harmonic Integrity: Free-floating the barrel under a rigid handguard reduces external pressures that can shift impact when you load a bipod or brace on a tripod.

• Repeatable Interface: Billet receivers and quality furniture produce a consistent cheek weld, trigger press, and support-hand position—the fundamentals that shrink groups.

Ideal Use Cases (Where Lawful)

• Varmints & Predators: Prairie dogs, coyotes, and farm pests where precision and follow-up speed matter.

• Target & Steel: PRS-style practice, club matches, and long-range days where a stable gas-gun shines.

• Ranch/Property: A dependable, accurate .308 for wide-open ground and wind.

Setup Tips for Best Performance

1. Optics: Pair with a 3-15×, 4-16×, or 5-25× scope in a quality one-piece mount; confirm torque and level.

2. Support: Add a swivel or cant-adjustable bipod at 6 o’clock; consider an Arca/M-LOK® plate for tripod work; keep a small rear bag in your pack.

3. Zero & Dope: Most shooters choose a 100-yard zero for precise data; true your ballistic solver with real chronograph velocities.

4. Ammo Vetting: Test multiple loads (e.g., 155–175gr match, 125–150gr varmint) and record group size, velocity (SD/ES), and POI—stick to one lot number for season consistency.

Specifications

• Manufacturer: Rock River Arms (RRA)

• Model: LAR-BT3 Varmint

• Caliber: .308 Winchester (consult owner’s manual regarding any 7.62×51 NATO use)

• Capacity: 20+1 (magazine dependent; observe local laws)

• Barrel: 20" stainless bull (heavy contour), free-float

• Handguard: 17" M-LOK® free-float

• Receivers: Billet upper & lower, black finish

• Stock: OEM NSP-2 carbine stock (adjustable)

• Grip: Hogue® OverMolded beavertail

• Controls: Standard AR layout (safety, mag release, bolt catch)

• Model #: XBT31521

• UPC: 842834119752

Exact trigger, gas system, and muzzle device may vary by production lot/dealer package—check your retailer’s listing for included components.

What’s in the Box*

• RRA LAR-BT3 Varmint .308 Win (20")

• (1) Magazine (type/capacity may vary by state/dealer)

• Owner’s manual & lock
  *Contents can vary by shipment; verify the retailer’s listing.

Care & Maintenance

• Break-In: Follow RRA’s recommended procedure for stainless barrels to speed seasoning and cleaning.

• BCG & Gas System: Keep the bolt carrier group lightly lubricated; inspect gas key screws and staking periodically.

• Fasteners: Re-torque rings, mounts, and M-LOK® hardware after the first live-fire session; use thread treatment as recommended.

• Cleaning Cadence: Stainless bores clean quickly—use a bore guide, quality solvent, and non-marring tools.

Safety & Compliance

• Know Your Laws: Magazine limits, feature restrictions, and hunting rules vary—confirm local/state/federal compliance before purchase and use.

• Safe Handling: Verify clear before cleaning or transport; use quality eye/ear protection and follow all range commands.

SEO-Friendly Keywords (Use Naturally on Your Product Page)

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**Built to hold tight when the barrel gets hot—**the RRA LAR-BT3 Varmint (.308 Win, 20" stainless bull, billet receivers) is a purpose-built accuracy rig that turns long strings into small groups and distant specks into clean hits.

The End