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BROWNELLS
M16 5.56 BOLT CARRIER GROUP NITRIDE MP

050806002371 078102001

Description
Ratings (13)

Reliability for the Discerning Operator

The Brownells Bolt Carrier Group is made by a well-established firearms industry manufacturer, made to our specifications. All components of the BCG are made in-house, under one roof, not outsourced to the lowest bidder. Even the firing pin and gas key, commonly outsourced components, are machined by our manufacturer. These Bolt Carrier Groups are rigorously inspected at the factory, for hardness requirements, fitment, cam path geometry, magnetic particle inspection of the bolt and more. Materials for these Bolt Carrier Groups are certified in batches and the dimensions are true to the most current military specifications. Proudly Made in the USA. Bolt is made from 9310 hardened steel, shot peened and magnetic particle inspected Carrier is machined from 8620 hardened steel Extractor is machined from 4340 steel and includes mil-spec extractor spring and black o-ring Gas Key is machined from 4130 steel and attached with Grade 8 screws, that are properly staked into a milled “valley” to ensure proper positioning Cam Pin is machined from hardened 4340 steel Firing Pin is made from 8740 steel, center-less ground and hard chrome coated Magnetic-particle inspected Bolt Extractor includes spring and rubber insert Includes torqued and staked gas key Functions with any cartridge based on the 5.56 NATO cartridge case The Brownells M16 5.56 Complete Bolt Carrier Group is designed to work easily and reliably in any AR-15 or M16 rifle chambered in 5.56x45mm, 300 AAC Blackout or .223 Remington. The Brownells M16 5.56 Complete Bolt Carrier Group comes with a bolt, bolt carrier, gas key, firing pin, cam pin and a firing pin retaining pin.

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Customer ratings for BROWNELLS M16 BOLT CARRIER GROUP 5.56X45MM NITRIDE MP

Number of ratings: 13
From brownells.com: 13
Average rating: 4.9

nice quality (19/08/2017)

Nice quality and well built part. The price made it a can't pass up deal.

Wow (22/08/2017)

The finish on this BCG is superb hands down the best buy at any price.

Good deal (08/10/2017)

I ordered one of these to use in a budget build of misc. parts that had been building up form other rifle upgrades.

I was surprised at the quality. This BCG looks and works great the finish and machining were surprising in a part in this price range. I will buy more of these as I need them.

Good To Go (19/11/2017)

I ordered two of these to finish a couple builds of mine. When I first got them I check them over because something this cheap can't be very good. I found the gas key was tight and the screws are properly staked. The bolt is marked MP and the gas rings are in spec. So far I've shot a few hundred rounds with them and I've had no problems so far. I'm planning on buying more in the near future.

Used in our production and Custom guns. (25/01/2018)

We use this Bolt Carrier Group in all our production and custom built 5.56 and .300 Blackout guns. We will use nothing else.

My number 1 choice for AR BCG! (31/01/2018)

Iâve installed this BCG in dozens of AR platforms with zero issues. This is my number 1 choice for BCG for an AR platform.

Top Notch (14/02/2018)

I have used these BCGs loyaly in my m16a1 and an xm177 clone builds. These things are staked properly and have had absolutley no failures upon first use and hundreds of rounds there after. Currently I have around 500 rounds through my a1 and the wear patterns on bcg are minimal/normal. However, I cannot say that this will work for someone running a different manufacture of charging handle/upper with their possible slight tolerance differences. Both my builds are running on Brownells uppers and charging handles and bumping into CMMG gas tubes. If you plan on doing a clone build or any other build and plan to use this BCG, you will be one happy guy/gal.

GREAT FIT HIGH QUALITY FOR LOW PRICE! (20/02/2018)

This BCG has one of the best finishes I've seen yet. Although it's not Chromed Lined the Nitride MP Finish should fill the gap. It slides nice and smooth in my upper while a Nickle Boron BCG was a little rough. I ran a few rounds and it's as smooth as a baby's behind!. A Great Buy for the money & I will suggest it to my friends also buy another for a future project....

<img width="500" src='/userdocs/reviewimages/aa05450a-47e8-4980-8453-b4e722bf1214.jpg' alt=''>

Great ar bolt carrier (23/03/2018)

Works 100% with my AR pistol and rifle

Best bang for the buck ! (25/04/2018)

This BSG is of a quality I have seen for well over $100. Smooth operation and quality built . The shipping was much faster than expected! Bravo , Brownells. you have a new loyal customer !

Outstanding BCG (14/07/2018)

The Black Nitride finish on this Bolt Carrier Group (BCG) is amazing. First the Nitride finish creates a smoother surface than phosphate coated bolts, Second this bolt wipes clean very easily, and third this Nitride BCG does not show signs of wear at the the same round counts as my phosphate coated bolts. You now have a budget priced BCG that performs like the the more expensive BCG finishes.

I've always bought the budget BCG. With this Brownell Nitrided M16 Bolt Carrier Group, I'm paying budget prices and getting high end quality. This is my new go to BCG.

Best BCG yet! (01/09/2018)

I have handled and used many BCGs over the years. Even an expensive BCG carrier had issues with not being finished smooth where the carrier interfaces with the face of the buffer. This resulted in dramatic gouging of the buffer face (yes it still worked but it should not have happened).

Enter the Brownells BCG. I have only fired a few hundred rounds, but the machining of all the parts is 100%. Even the locking lugs on the bolt have a slight angled cut on the back of each locking lug to aid in even smoother lockup.

I used to be of the mindset that a BCG that wasn't at least 130 or more......was garbage.

Any future BCG will be a Brownells (Toolcraft is also an equivalent value and quality, but Brownells wins still). I do Like to run a JP bolt as well, to get extra fancy :)

Excellent M16 Bolt Carrier Group (24/09/2018)

The Brownells M16 Bolt Carrier Group is an excellent buy! I made some random measurments and each one met Mil Spec dimensions. The Timing was also checked with Upper installed and the Bolt Assembly locked at correct time. This is highly recommended!

Read 13 more ratings on brownells.com

129.9 129.9 1 GBP

Product no.: 078102001
BROWNELLS M16 BOLT CARRIER GROUP 5.56X45MM NITRIDE MP
Mfr Part: AZT-M4-556-ST-0 050806002371 The Brownells M16 5.56 Complete Bolt Carrier Group is designed to work easily and reliably in any AR-15 or M16 rifle chambered in 5.56x45mm, 300 AAC Blackout or .223 Remington. The Brownells M16 5.56 Complete Bolt Carrier Group is constructed with a bolt made from 9310 steel, which is finished with a heat treatment and shot peening. The carrier is fabricated from 8620 hardened steel. Each element of the bolt-carrier group is finished in a black-nitride coating. Magnetic-particle inspected material Extractor includes spring and rubber insert Includes torqued and staked gas key Functions with any cartridge based on the 5.56 NATO cartridge case The Brownells M16 5.56 Complete Bolt Carrier Group comes with a bolt, bolt carrier, gas key, firing pin, cam pin and a firing pin retaining pin.

129.9 GBP 442 £129.90 *

Is a 'Call to order' product.

Not available.

Specs: Cartridge: 5.56 mm NATO Finish: Black Nitride Make: AR-15

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Is a 'Call to order' product.

Top takeaways

The Brownells M16 5.56 Complete Bolt Carrier Group is compatible with AR-15 or M16 rifles and functions with 5.56x45mm, 300 AAC Blackout, or .223 Remington cartridges.
Constructed with a 9310 steel bolt and 8620 hardened steel carrier, it features a black-nitride finish and includes a magnetic-particle inspected material for reliability.
This bolt carrier group comes with all necessary components, including a bolt, carrier, gas key, firing pin, cam pin, and firing pin retaining pin, with the extractor having a spring and rubber insert.

Description

The Brownells M16 5.56 Complete Bolt Carrier Group is designed to work easily and reliably in any AR-15 or M16 rifle chambered in 5.56x45mm, 300 AAC Blackout or .223 Remington. The Brownells M16 5.56 Complete Bolt Carrier Group is constructed with a bolt made from 9310 steel, which is finished with a heat treatment and shot peening. The carrier is fabricated from 8620 hardened steel. Each element of the bolt-carrier group is finished in a black-nitride coating. Magnetic-particle inspected material Extractor includes spring and rubber insert Includes torqued and staked gas key Functions with any cartridge based on the 5.56 NATO cartridge case The Brownells M16 5.56 Complete Bolt Carrier Group comes with a bolt, bolt carrier, gas key, firing pin, cam pin and a firing pin retaining pin.

Attributes

Cartridge: 5.56 mm NATO Finish: Black Nitride Make: AR-15 Delivery weight: 0.329kg Shipping height: 25mm Shipping width: 38mm Shipping length: 184mm UPC : 050806002371

Item details

Made in USA
US export classification: I(g)

Upgrade your AR-15 with the Brownells M16 5.56 Bolt Carrier Group. 🔧 Reliable, durable, and perfect for 5.56 NATO cartridges!

Description
Ratings (13)

Reliability for the Discerning Operator

More...

Customer ratings for BROWNELLS M16 BOLT CARRIER GROUP 5.56X45MM NITRIDE MP

Number of ratings: 13
From brownells.com: 13
Average rating: 4.9

nice quality (19/08/2017)

Nice quality and well built part. The price made it a can't pass up deal.

Wow (22/08/2017)

The finish on this BCG is superb hands down the best buy at any price.

Good deal (08/10/2017)

Good To Go (19/11/2017)

Used in our production and Custom guns. (25/01/2018)

We use this Bolt Carrier Group in all our production and custom built 5.56 and .300 Blackout guns. We will use nothing else.

My number 1 choice for AR BCG! (31/01/2018)

Iâve installed this BCG in dozens of AR platforms with zero issues. This is my number 1 choice for BCG for an AR platform.

Top Notch (14/02/2018)

GREAT FIT HIGH QUALITY FOR LOW PRICE! (20/02/2018)

Great ar bolt carrier (23/03/2018)

Works 100% with my AR pistol and rifle

Best bang for the buck ! (25/04/2018)

This BSG is of a quality I have seen for well over $100. Smooth operation and quality built . The shipping was much faster than expected! Bravo , Brownells. you have a new loyal customer !

Outstanding BCG (14/07/2018)