Rock River Arms AR0598.V1 LAR-15M Upper, .223 Wylde, 18-inch Stainless

The Rock River Arms AR0598.V1 LAR-15M All Terrain Hunter Complete Upper is a factory-configured AR upper intended for field and range use where consistent performance is required. It is chambered in .223 Wylde and pairs an 18-inch stainless heavy match barrel with a free-float M-LOK handguard. This upper ships assembled and includes a bolt carrier group and charging handle for immediate integration onto a compatible lower receiver.

Key Specifications

• Chambered for .223 Wylde to accommodate .223 and 5.56mm ammunition.
• The barrel measures 18 inches overall for extended velocity and stability.
• Barrel finish is Stainless Steel for corrosion resistance and consistent appearance.
• Barrel construction uses Steel with a heavy match profile.
• The barrel profile is specified as Heavy match-grade for improved harmonics.
• Rate of twist is 1:8 to stabilize a wide range of bullet weights.
• Handguard is a 13-inch M-LOK extended free-float rail for accessory mounting.
• Handguard and receiver finish are Black.
• Equipped with the RRA Operator muzzle brake / 1/228 thread as specified by the manufacturer.
• Includes a bolt carrier group and charging handle for a complete upper assembly.

This complete upper brings together components selected for real-world use—an 18-inch heavy match barrel and a long, M-LOK-compatible free-float handguard—making it suitable for precision-oriented field work and extended-range shooting. The factory assembly and included bolt carrier group simplify installation onto a compatible lower, delivering a ready-to-fit option for shooters seeking a purpose-built upper without additional part sourcing.