Rock River Arms BT-3 Completed Upper Receiver 6.5mm Creedmoor 28in 20in Barrel Standard SS Fluted Profile 1-10 Twist 5/8x24 Thread M-LOK Handguard

2 options

28" · 20", this page
32" · 24"out of stock

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Rock River Arms

Overview

The Rock River Arms BT-3 Completed Upper Receiver is designed for precision shooting with its 28-inch barrel chambered in 6.5 Creedmoor, known for its long-range capabilities and accuracy. The 1:10 twist rate optimizes stability for various bullet weights, while the 5/8x24 thread pitch allows for easy attachment of muzzle devices. This upper receiver is ideal for precision builds where performance at distance is a priority.

Specifications

MPN65C0567BT

Twist Rate1:10

Thread Pitch5/8x24

Barrel Length20

AssemblyComplete

PlatformAR-10

Caliber6.5 Creedmoor

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Rock River Arms BT-3 Completed Upper Receiver 6.5mm Creedmoor 28in 20in Barrel Standard SS Fluted Profile 1-10 Twist 5/8x24 Thread M-LOK Handguard

2 options

28" · 20", this page
32" · 24"out of stock

Available Merchants(1)

Prices checked Oct 11, 2026

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Optics Planet

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$1,079

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Build history on GunPartPicker

Builders on GunPartPicker first added the Rock River Arms BT-3 Completed Upper Receiver 6.5mm Creedmoor 28in 20in Barrel Standard SS Fluted Profile 1-10 Twist 5/8x24 Thread M-LOK Handguard to a build in March 2026.

Today the one retailer we track is out of stock. Listed prices start at $1,079 at Optics Planet for when it comes back.

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