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BROWNELLS
M16 MIL-SPEC MP BOLT CARRIER GROUP

050806110977 078000250

Description
Ratings (10)

Complete M16 Bolt Carrier Group: Fully assembled Bolt Carrier Group; including the bolt, bolt carrier, gas key, firing pin, cam pin, and firing pin retaining pin Every Bolt is Magnetic Particle Inspected (MPI) The Bolt is machined from Carpenter 158 steel Following machining, the Bolt is heat treated and shot peened Installed extractor includes red o-ring with spring M16 Bolt Carrier is machined from 8620 steel and hardened Interior of Bolt Carrier Carrier Key & Bolt Carrier are chrome lined on the M16 Phosphate Bolt Carrier Group only M16 Bolt Carrier will function in semi-auto or full-auto AR-15/M16 Gas Key Screws are properly torqued and staked Bolt and Bolt Carrier feature a matte black mil-spec finish

SPECS: Bolt – Carpenter 158 steel, Magnetic Particle Inspected, High Pressure Tested. Carrier – 8620 hardened steel, M16. Matte black phosphate finish.

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Customer ratings for BROWNELLS M16 PHOSPHATE BOLT CARRIER GROUP MP C158

Number of ratings: 10
From brownells.com: 10
Average rating: 4

M16 nitride (17/11/2015)

Bought on sale for $99! very nice! M16 nitride BCG! Very slick finish! Well staked! The entire BCG is nitride! Including the inside of bolt carrier and gas key! The only thing that was not nitride was the firing pin! This BCG does not have a chrome inner lining! .... If you're looking for that!

Bolt is Marked....mpi and Hpt!

Excellent! (24/12/2015)

Purchased for a recent build using a nitrided barrel from Daniel defense and a nitrided gas tube from spikes tactical. My only regret: I didn't buy TWO (for a 300 blackout build) at $99+shipping.

Good Quality (28/12/2015)

Well made Nitride finished BCG. I got it on sale and was very pleased with the quality. Oiled it up, slapped it in the upper and away it went. No problems.

Updated review (15/02/2016)

I just noticed I mistakenly clicked on "no, I would not recommend to a friend" this is a correction. All else I said before stands.

Good bolt (21/12/2016)

I got a bad bolt the first time but luckily brownells has the easiest return policy I've ever come across. Got a new one and it fit great.

Good even nitride treatment, bad parts (29/01/2017)

I've shot about 1850 rounds through this bolt and it has a week ejector spring.

Defective (15/08/2018)

BCG arrived and was installed in a target gun. It lasted for around 4 months with light use (200-400 rounds a week). Started experiencing failure to eject malfunctions. Upon inspection the ejector spring had fallen out. I warranty'd the part out and will try again.

I will always use Brownells for 90% of my parts. This one just was a fluke...

Disappointing (14/02/2017)

Bought this BCG for my DMRish build. It's going to be a special gun, so expense was really not an issue. Took a flyer on a Brownells BCG because I had (and still have) a lot of faith in Brownell's quality.

When it became time to start assembly of the upper, I became very concerned about the quality of the BCG. Two issue immediately came to the fore: the very rough, difficult movement of the bolt and the firing pin retention pin. The bolt drags, and no amount of oil or grease eased it. I work at a gun store, and none of the AR-15s tried, even the cheapest DPMS, exhibits this type of difficult movement.

The second issue was uncovered when I disassembled the BCG. The firing pin retaining cotter pin was malformed. The two legs are spread quite wide, which makes resembling the BCG difficult and time consuming. I've never encountered this type of flaw before.

I'm not waiting for a third strike, not with the money invested in the gun, it's going back to Brownells.

An aside: I also used the Brownells Lower Parts Kit: also unimpressed with it's quality. Although, Brownells upper part kit was fine.

To the good, Brownells return process was quick and easy. The BCG is on its way back. I remain a huge fan of Brownells.

Quality BCG (06/03/2017)

Not my first build. Putting together a 20" varmint/target rifle, I chose this BCG and am very happy with the choice. I did however notice that the bolt was tight inside the carrier, the bolt support was also phosphate coated. NOT a problem, just oiled the rings and bolt support and worked it back and forth "clean and reoil often" and this seated everything nicely. Installed in a Stag upper with a VLTOR gunfighter handle "also a great choice" and could not get over how silky-smooth the action was. 500rds and still very happy.

Not the quality it should be (22/05/2017)

Purchased 2 of these on 2 different orders, both failed after 200-250 rds. I originally thought the gas rings were bad "bolt was loose in carrier " but that wasn't the case. The carriers were not chrome lined or not done properly. Not bashing Brownells in any way, could have been a bad production run from supplier. I upgraded to the Bravo Company BCG and they are very nice. The return was simple and painless. A+++ to their customer service. I have used Brownells alot and they will remain my go to shop.

Read 10 more ratings on brownells.com

174.9 174.9 1 GBP

Product no.: 078000250
BROWNELLS M16 PHOSPHATE BOLT CARRIER GROUP MP C158 050806110977 Complete M16 Bolt Carrier Group: Fully assembled Bolt Carrier Group; including the bolt, bolt carrier, gas key, firing pin, cam pin, and firing pin retaining pin Every Bolt is High Pressure Tested (HPT) with a proof load Following the High Pressure Test, every Bolt is Magnetic Particle Inspected (MPI) Not stamped with HPT or MPI The Bolt is machined from Carpenter 158 steel Following machining, the Bolt is heat treated and shot peened Installed extractor includes red o-ring with spring M16 Bolt Carrier is machined from 8620 steel and hardened Interior of Bolt Carrier Carrier Key & Bolt Carrier are chrome lined on the M16 Phosphate Bolt Carrier Group only M16 Bolt Carrier will function in semi-auto or full-auto AR-15/M16 Gas Key Screws are properly torqued and staked Bolt and Bolt Carrier feature a matte black mil-spec finish

174.9 GBP 28 £174.90 *

Is a 'Call to order' product.

Not available.

Specs: Cartridge: 223 Remington, 5.56 mm NATO, 300 AAC Blackout Finish: Matte Black, Phosphate Make: AR-15

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Restrictions

Is a 'Call to order' product.

Top takeaways

The bolt carrier group is fully assembled, including all necessary components and is suitable for AR-15, 5.56 NATO, and 300 AAC Blackout firearms.
Each bolt undergoes High Pressure Testing and Magnetic Particle Inspection to ensure quality, although they are not stamped with HPT or MPI.
The bolt is made from Carpenter 158 steel and the M16 carrier from 8620 steel, both featuring a matte black phosphate finish for durability.

Description

Complete M16 Bolt Carrier Group: Fully assembled Bolt Carrier Group; including the bolt, bolt carrier, gas key, firing pin, cam pin, and firing pin retaining pin Every Bolt is High Pressure Tested (HPT) with a proof load Following the High Pressure Test, every Bolt is Magnetic Particle Inspected (MPI) Not stamped with HPT or MPI The Bolt is machined from Carpenter 158 steel Following machining, the Bolt is heat treated and shot peened Installed extractor includes red o-ring with spring M16 Bolt Carrier is machined from 8620 steel and hardened Interior of Bolt Carrier Carrier Key & Bolt Carrier are chrome lined on the M16 Phosphate Bolt Carrier Group only M16 Bolt Carrier will function in semi-auto or full-auto AR-15/M16 Gas Key Screws are properly torqued and staked Bolt and Bolt Carrier feature a matte black mil-spec finish

Attributes

Cartridge: 223 Remington,5.56 mm NATO,300 AAC Blackout Finish: Matte Black,Phosphate Make: AR-15 Delivery weight: 0.318kg Shipping height: 33mm Shipping width: 203mm Shipping length: 305mm UPC : 050806110977

Item details

Made in USA
US export classification: I(g)

Upgrade your AR-15 with the Brownells M16 MIL-SPEC Bolt Carrier Group! 🔧 High Pressure Tested & Magnetic Particle Inspected for reliability.

Description
Ratings (10)