AR-15 Bolt Carrier Group 5.56X45mm Nitride MP

Best price

$94.99at Brownells

checked Sep 30, 2026

Buy at Brownells

Where to buy

Store	Price	Availability	Buy	Add to build
Brownells	$94.99checked Sep 30, 2026	Check store	Buy at Brownells

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About this part

The AR-15 Bolt Carrier Group 5.56X45mm Nitride MP is a 5.56 / .223 bolt carrier group from Brownells. One store lists it, Brownells at $94.99.

Fits and works with

Caliber: 5.56 / .223 · Shop matching ammo
Bolt: Standard AR-15 (5.56 / 300 BLK / .350 Legend) · Bolt carrier groups

Specifications

Manufacturer: Brownells
Platform: AR-15
Caliber: 5.56 mm NATO

From the manufacturer

A Bolt-Carrier Group Purpose-Built to Run Reliably in Your AR-15

Whether you're looking to finish off a new AR-15 build or you need a spare bolt-carrier group to have on-hand as a ready replacement (always a good idea), Brownells has you covered with its AR-15 Bolt Carrier Group. This ready-to-roll BCG is built to provide dependable operation in any AR-15 chambered in 5.56 NATO, .223 Remington or 300 Blackout.

Each Brownells AR-15 Bolt-Carrier Group features a bolt machined from 9310 tool steel, which is heat-treated and shot-peened. The carrier itself is machined from 8620 hardened steel. Both of these components, as well as every other part in the bolt-carrier group, are finished in a nitride coating. Every bolt is magnetic-particle inspected and features a torqued-and-staked gas key.

With each Brownells AR-15 Bolt-Carrier Group, you'll receive the bolt, bolt carrier, gas key, firing pin, cam pin, firing pin retaining pin and an extractor with the necessary spring and rubber insert. This bolt-carrier group will work with any cartridge based on the 5.56 NATO case, and it is not designed for use in full-auto lower receivers.