Rock River Arms LAR-15M CLB Complete Upper 458 SOCOM 16″ Chrome Moly Bull Barrel with 13″ M-LOK Handguard

The Rock River Arms LAR-15M CLB Complete Upper (SOC0820V1) is chambered in 458 SOCOM and built around a 16-inch chrome moly bull barrel with a 1:14 twist rate. The upper receiver is a forged A4 design and is compatible with AR-15 lower receivers.

The muzzle is threaded 5/8x32 and fitted with the RRA Beast Brake. Gas operation uses a low-profile gas block. The handguard is an RRA lightweight aluminum free-float rail in an extended 13-inch length with M-LOK compatibility.

Key Features

• Caliber: 458 SOCOM
• Barrel: 16-inch chrome moly bull barrel, 1:14 twist
• Upper receiver: Forged A4
• Muzzle device: RRA Beast Brake, 5/8x32 thread
• Gas block: Low-profile
• Handguard: RRA lightweight aluminum free-float rail, 13-inch extended length, M-LOK compatible
• Includes bolt carrier group and charging handle assembly
• Fits AR-15 lower receivers

This is a complete upper assembly — the bolt carrier group and charging handle are included. It is designed to fit standard AR-15 lower receivers, making it a drop-in addition for builders working with an existing lower.

ICB Firearms carries Rock River Arms products and ships nationwide. Local pickup is available at our Saint Clair Shores, Michigan location.