Rock River Arms Completed Upper Receiver Predator HP A4 .308/7.62X51mm NATO 20 Inch Barrel 1-10 Twist Free-Float Handguard Brake Black

2 options

16"out of stock
20", this page

Rock River Arms Completed Upper Receiver Predator HP A4 .308/7.62X51mm NATO 20 Inch Barrel 1-10 Twist Free-Float Handguard Brake Black - Upper Receiver for AR-15 - view 1

Click to see full view

Rock River Arms

Overview

The Rock River Arms Completed Upper Receiver Predator HP A4 is a fully assembled upper designed for the AR-10 platform, featuring a 20-inch barrel chambered in 7.62x51 NATO with a 1:10 twist rate. The A4 receiver type provides a reliable foundation for various optics and accessories, while the black finish offers a sleek, tactical appearance. This upper is commonly found in precision and long-range builds, where the longer barrel length aids in accuracy and stability.

Specifications

MPN308A0567

Twist Rate1:10

ColorBlack

Barrel Length20

AssemblyComplete

PlatformAR-10

Caliber7.62x51 NATO

Receiver TypeA4

Receiver PatternRock River LAR-8

Visit the Rock River Arms Store All Rock River Arms upper receivers

Rock River Arms Completed Upper Receiver Predator HP A4 .308/7.62X51mm NATO 20 Inch Barrel 1-10 Twist Free-Float Handguard Brake Black

2 options

16"out of stock
20", this page

Available Merchants(1)

Prices checked Oct 11, 2026

Stock Alert

Get an email when this is back in stock.

Optics Planet

Free shipping

Shipping Speed

Out of Stock

$900

Buy Now

September 2026 on GunPartPicker

Rock River Arms Completed Upper Receiver Predator HP A4 .308/7.62X51mm NATO 20 Inch Barrel 1-10 Twist Free-Float Handguard Brake Black ranked #267 of the 615 upper receivers builders added on GunPartPicker in September 2026.

Today the one retailer we track is out of stock. Listed prices start at $899.99 at Optics Planet for when it comes back.

Trending upper receivers →

Updated Oct 11, 2026 · from real builds on GunPartPicker · Prices checked Oct 11, 2026 · refreshed daily across 37 retailers