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BROWNELLS
M16 5.56 BOLT CARRIER GROUP NICKEL BORON MP

508061122858 078102002

Description
Ratings (7)

Flawless Operation at an Affordable Price

The Brownells M16 5.56 Complete Bolt Carrier Group is an affordable option that is built and tested to provide flawless operation in any AR-15 or M16. The Brownells M16 5.56 Complete Bolt Carrier Group features a bolt fabricated from 9310 steel that includes a heat-treated and shot-peened finish. The bolt carrier itself is built using 8620 steel, which features a hardened finish. The whole BCG is completed with a nickel-boron coating. Steel quality assured with magnetic particle inspection Features extractor with rubber insert and spring Gas-key screws are torqued and staked Designed for use with all 5.56-NATO-based cartridge cases. The Brownells M16 5.56 Complete Bolt Carrier Group features a full assembly that includes the 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 NI BORON MP

Number of ratings: 7
From brownells.com: 7
Average rating: 3.6

Quality on a budget. (25/06/2017)

Comes in an matte grey color, with the coating all around and inside the carrier and bolt. Cotter pin, and gas keys are not treated and are the typical black.

I put it in a 10.5 inch upper with carbine gas system and standard carbine buffer and spring. Ate through 500 rounds in one session like nothing.

Only required minimal lube, the carbon wiped almost completely off with a paper towel. Finish is pretty solid, not much sign of wear after 500 rounds. And very slick, pretty much never needed to use forward assist on press checks because the bolt slides in very smoothly (as any bcg should but some fail at even that). Staking on the gas key is perfectly adequate. M4A1 o ring on the exractor. Gas rings on bolt provide very good seal (bolt is snug inside carrier)

All these things are to be expected of a typical milspec bolt carrier group. But holy moly, the price brownells is letting it go for gets it that 5th star. Absolutely worth it in budget project builds and high end builds alike. Cant say for sure if it can outlast/outperform a bcm, daniel defense, or other pricier bcg, but definately worth a try.

Ready to go (13/07/2017)

Dropped right in to my S&W AR15 Sport. Pre-lubed and ready to go. Finish looks great and can't beat the price.

Great value and quality (19/07/2017)

This BCG is very high quality for the money you pay. Brownells can offer the quality at this price. You really can't beat it.

Great deal (07/09/2017)

Form, fit, and function are flawless! Very few machining marks remain and the are not anyplace important. Coating is well done. Bolt teeth are sharp and clean. This is a well done bolt at a great price (got it on sale) and I wish I'd ordered a few!

needs better finishing (31/12/2017)

good deal nickel finish is good but needed tooling cleaned up before it was plated its really rough but nothing other then looks and cleaning would be an issue

You Get What You Pay For (03/01/2018)

First off let me say I bought this item on sale and with a coupon bring the price that of a budget nitride BCG so I wasnât expecting too much. After the first 100 rounds it developed a black stain to it as you can see in the pictures. After the next 400 rounds I noticed the charging handle was hard to pull back, the bolt wasnât unlocking very easily. I pulled the BCG out to clean it up thinking that would fix it (it did) however I noticed the left lower carrier rail was very jagged and sharp. This is not OK as the sharp and harder steel will chew away at the softer aluminum upper receiver. For what I thought was an OK BCG for a failure like this after 500 rounds of factory ammo is not OK.

<img width="500" src='/userdocs/reviewimages/0007e7e6-d0bc-4c0e-a299-4c481f4a1cff.jpg' alt=''>

<img width="500" src='/userdocs/reviewimages/ec574648-82a5-40c1-a345-10379ee6bd89.jpg' alt=''>

<img width="500" src='/userdocs/reviewimages/13136651-afe8-48e3-860b-5ff1fc46f62a.jpg' alt=''>

<img width="500" src='/userdocs/reviewimages/36e836ee-1543-4818-af29-2114a146967c.jpg' alt=''>

Thin Coating; possibly out of spec. (06/08/2018)

Purchased this to replicate the bolt carrier of the XM16E1. This bolt carrier seemed to be a good match to the finish and look of the original carriers. However the finish is extremely thin and doesn't clean easily. After taking this rifle to the range and firing only 100 rounds of good brass ammo; the bolt became very stiff to pull back with the charging handle. After disassembling it; there was an extreme buildup of carbon within the carrier body. The carrier was also stained by Carbon and has bad rubbing marks on the side of it--which makes me think it's slightly out of spec. The carrier has since been replaced.

Read 7 more ratings on brownells.com

149.65 149.65 1 GBP

Product no.: 078102002
BROWNELLS M16 BOLT CARRIER GROUP 5.56X45MM NI BORON MP
Mfr Part: AZT-M4-556-ST-0 508061122858 The Brownells M16 5.56 Complete Bolt Carrier Group is an affordable option that is built and tested to provide flawless operation in any AR-15 or M16. The Brownells M16 5.56 Complete Bolt Carrier Group features a bolt fabricated from 9310 steel that includes a heat-treated and shot-peened finish. The bolt carrier itself is built using 8620 steel, which features a hardened finish. The whole BCG is completed with a nickel-boron coating. Steel quality assured with magnetic particle inspection Features extractor with rubber insert and spring Gas-key screws are torqued and staked Designed for use with all 5.56-NATO-based cartridge cases. The Brownells M16 5.56 Complete Bolt Carrier Group features a full assembly that includes the bolt, bolt carrier, gas key, firing pin, cam pin and a firing pin retaining pin.

149.65 GBP 881 £149.65 *

Is a 'Call to order' product.

Not available.

Specs: Cartridge: 5.56 mm NATO Finish: Nickel-Boron 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 designed for reliable performance in AR-15 or M16 rifles, with a bolt made from 9310 steel and a carrier from 8620 steel, both heat-treated for durability.
It features a nickel-boron coating for reduced friction and easy cleaning, and includes a full assembly with all necessary components like the gas key and firing pin.
The bolt carrier group undergoes magnetic particle inspection to ensure steel quality, and has an extractor with a rubber insert and spring for consistent extraction.

Attributes

Cartridge: 5.56 mm NATO Finish: Nickel-Boron Make: AR-15 Delivery weight: 0.329kg

Item details

Made in USA
US export classification: I(g)

🌟 Upgrade your AR-15 with the Brownells M16 Bolt Carrier Group! Nickel-Boron finish for reliability. Perfect for 5.56 NATO. Shop now for peak performance! 🔧🛒

Description
Ratings (7)

Flawless Operation at an Affordable Price

More...

Customer ratings for BROWNELLS M16 BOLT CARRIER GROUP 5.56X45MM NI BORON MP

Number of ratings: 7
From brownells.com: 7
Average rating: 3.6

Quality on a budget. (25/06/2017)

Ready to go (13/07/2017)

Dropped right in to my S&W AR15 Sport. Pre-lubed and ready to go. Finish looks great and can't beat the price.

Great value and quality (19/07/2017)

This BCG is very high quality for the money you pay. Brownells can offer the quality at this price. You really can't beat it.

Great deal (07/09/2017)

needs better finishing (31/12/2017)

good deal nickel finish is good but needed tooling cleaned up before it was plated its really rough but nothing other then looks and cleaning would be an issue

You Get What You Pay For (03/01/2018)

Thin Coating; possibly out of spec. (06/08/2018)

Read 7 more ratings on brownells.com

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