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BROWNELLS
308AR BOLT CARRIER GROUPS

508061123398 078102004

Description
Ratings (13)

The Ideal Big-Bore Bolt Carrier Group

The Brownells Complete .308 Bolt Carrier Group is designed to operate reliably in DPMS LR-308 pattern rifles chambered in .308, .243, 7mm-08, .338 Federal, .260 Remington, 6.5mm Creedmoor, or any other cartridge based on the .308 Winchester. These BCGs are manufactured to the same uncompromising standards as our M16-style BCGs. Our Complete .308 Bolt Carrier Group has a bolt machined from robust 9310 steel, heat-treated and shot-peened for superb hardness. The carrier itself is fabricated from hardened 8620 steel. Both are magnetic particle inspected (MPI) to make sure there are no hidden microscopic flaws that could lead to premature failure. Carrier has forward assist notches Extractor is installed with rubber insert and spring Gas key screws are torqued and staked For use in DPMS LR-308 pattern upper receivers only; NOT compatible with Armalite rifles You can get the Brownells Complete .308 Bolt Carrier Group with a hard Black Nitride finish that is exceptionally resistant to surface wear OR a Nickel Boron coating (a dull matte silver) that’s even harder and self-lubricating to boot. Both come complete with firing pin, firing pin retaining pin, cam pin, gas rings, gas key, extractor, and ejector installed. Brownells GunTech™ Note: Unlike BCGs with a traditional Parkerized finish, the carrier on our Black Nitride bolt carrier group is not hard-chromed inside because Nitride is actually harder than industrial chrome plating.

More...

Customer ratings for BROWNELLS 308AR BOLT CARRIER GROUP 308 WIN NITRIDE MP

Number of ratings: 13
From brownells.com: 13
Average rating: 4.5

Great BCG (09/03/2018)

I bought this for my Aero Precision M5 build, and although Iâm only half way through, this bolt looks great. Thereâs no sharp corners or edges and looks very well crafted. Thanks Brownells.

<img width="500" src='/userdocs/reviewimages/a70a6c45-acb7-49ba-a10f-62d1cd91fda0.jpg' alt=''>

Impeccable quality and unbeatable price (25/03/2018)

Got this BCG the other day for my Aero M5 build. The machining on this bolt is superb. Their are no sharp edges anywhere. I have not shot this but I do have previous experience with their AR-15 M16 nitride bolt, which runs flawlessly, and will continue to do business with brownells. I know the .308 is a completely different animal when it comes to parts but the quality of their products are barnone. This will hopefully be mating up with a ballistic advantage DPMS cut barrel extension. Canât wait to get this rifle barking.

Dimensions Wrong Affecting Headspace (06/04/2018)

Actually Zero Stars - It was pretty, but on my specimen of this bolt, the individual bolt lugs measured .308" to .309" long and the bolt face recess measured .123" deep, which resulted in the bolt failing to reject a top quality NOGO gage in a well respected, high-end barrel brand. (WIN 308 headspace is 1.6300" to 1.6340", only .0040" total tolerance range and the barrel/extension combo gets part of that). I tried bolts from three other rifles in my shop and all firmly rejected the NOGO gage in this barrel. I talked with a Brownells' tech and he told me the lugs should be .312" and the recess should be .128" according to their manufacturer. My measurements showed this bolt to be way off the manufacturer dimensions. In my opinion, even if it were correct to the manufacturer's dimensions, it would likely still fail on the NOGO gage based on my experience (bolt face recess too deep). On many other AR-308 bolts and barrels used, I have found that bolt lugs measuring .312" to .313" long and bolt face recesses measuring .1245" to .1255" deep will headspace properly in good quality barrels. There is some info to support these dimensions on the web, but I could find no manufacturer dimensions. Rifle building hobbyists, BEWARE, there is no MIL SPEC for AR-308 rifles or parts, like on M4 and M16 parts used in AR-15s. Each AR-308 part maker chooses his own dimensions and tolerances. Every bolt/barrel combination should be headspaced for best quality, accuracy, and safety.

Nice Bolt but needs some TLC (11/04/2018)

I have several of these bolts and have had the same issue with both of them. Looking at the bolt face of the Extractor, the bevel on the Extractor does not line up with the diameter of the bolt recess. With the Extractor bevel not in the correct place the round is picked up and slammed into the chamber. The Extractor does not catch the edge of the shell and will not eject the shell. A simple fix is to remove the Extractor and increase the bevel so it will slip over the shell and seat it in the bolt recess. A good value BCG but not Military Spec. After the modification the bolt works without issue.

Decent for the money (17/04/2018)

I purchased the BCG for a build off an Aero Upper and Lower set.

The BCG is nice for the money, however my gas key hole was .007" undersized which resulted in the destruction of a gas tube. Fortunatly I had a reamer (.1805") for gas tubes and was able to use the reamer to bring the gas key into spec.

I chambered and headspaced the barrel to this bolt with no problems and once I get the kinks worked out I believe this rifle will be very reliable and long lasting.

Overall I am happy with the bolt due to its price point and decent quality. I believe I got a gas key that simply had a little build up of NiB in the bore causing it to be out of spec.

I spoke to tech support about this issue and they were very helpful and willing to exchange it immediately, however I want to try and make this one work due to my barrel being headspace to this bolt.

Quality product (07/05/2018)

I was having headspace problem with my new build, aero M5E1 upper, ballistic advantage barrel & a aero precision bolt, while using a forster headspace guage the bolt would not turn on the GO guage so I decided to swap the bolt for the brownell's nickle boron & it worked perfect. Ran about 150 rounds (6.5 creedmore) & it worked flawless, no jams/malfunction what so ever, only downside is when I received the bolt it was full but after polishing it was amazing.

Runs great in DPMS Pattern 308 AR (01/09/2018)

I helped a couple of buddies put together their AR-10's. They asked me to select all of the components as they had no experience building ARs. They used these BCG's. I helped them build the rifles, we took them to the range and they both performed great. They are shooting their rifles often and they are running great with this BCG,

<img width="500" src='/userdocs/reviewimages/7dc07657-2193-4233-9b16-23f952ff9bbc.jpg' alt=''>

<img width="500" src='/userdocs/reviewimages/894c1586-1f6a-4196-9e1e-f230da788219.jpg' alt=''>

Awesome (20/06/2017)

This bolt is made of the same high quality material as other more expensive ones. Fit and finish are top notch. Headspaced to my Ballistic Advantage 6.5 Creedmoor barrel perfectly. Haven't shot it yet, but the first impressions are phenominal.

Excellent! (09/09/2017)

The nitride finish is perfect. Functions flawlessly in my 6.5 Creedmoor with Ballistic Advantage barrel. Forward Assist serrations are on this bolt carrier and work as expected.

Great product. Thanks Pete.

Awesome, must have (17/12/2017)

This carrier is made so well, the machining and finish are perfect, smooth, slick, no machining/ tool marks, no burrs. No sharp edges, fits perfect

I'm super impressed, and I'm a machinist, I haven't seen any others better than this in any way

Go brownells!!!!!!!!!

Runs great (02/01/2018)

Runs flawlessly in my PSA10 gen 2. Itâs runs smooother than the original bolt Carr group.

Fine Looking BCG (28/07/2018)

Good Looking BCG, packaged good and shipped quick, I was glad to see a JP style firing pin retaining pin on this BCG, GOOD Value on the sale price...

Awesome 308 BCG (11/09/2018)

Wow! Just wow! Purchased for use in an Aero Precision M5 build. Finish is flawless. Cycle smoothly. Every bit as nice as a genuine Aer BCG, but at a much better price. Don't think twice, just buy it.

Read 13 more ratings on brownells.com

229.9 254.9 2 GBP

Product no.: 078102004
BROWNELLS 308AR BOLT CARRIER GROUP 308 WIN NITRIDE MP
Mfr Part: AZT-A10-308-ST- 508061123398 The Brownells Complete .308 Bolt Carrier Group is designed to operate reliably in DPMS LR-308 pattern rifles chambered in .308, .243, 7mm-08, .338 Federal, .260 Remington, 6.5mm Creedmoor, or any other cartridge based on the .308 Winchester. These BCGs are manufactured to the same uncompromising standards as our M16-style BCGs. Our Complete .308 Bolt Carrier Group has a bolt machined from robust 9310 steel, heat-treated and shot-peened for superb hardness. The carrier itself is fabricated from hardened 8620 steel. Both are magnetic particle inspected (MPI) to make sure there are no hidden microscopic flaws that could lead to premature failure. Carrier has forward assist notches Extractor is installed with rubber insert and spring Gas key screws are torqued and staked For use in DPMS LR-308 pattern upper receivers only; NOT compatible with Armalite rifles You can get the Brownells Complete .308 Bolt Carrier Group with a hard Black Nitride finish that is exceptionally resistant to surface wear OR a Nickel Boron coating (a dull matte silver) that’s even harder and self-lubricating to boot. Both come complete with firing pin, firing pin retaining pin, cam pin, gas rings, gas key, extractor, and ejector installed. Brownells GunTech™ Note: Unlike BCGs with a traditional Parkerized finish, the carrier on our Black Nitride bolt carrier group is not hard-chromed inside because Nitride is actually harder than industrial chrome plating.

229.9 GBP 233 £229.90 *

Is a 'Call to order' product.

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Specs: Cartridge: 308 Winchester Finish: Black Nitride Make: AR .308

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Restrictions

Is a 'Call to order' product.

Top takeaways

The Brownells Complete .308 Bolt Carrier Group is compatible with DPMS LR-308 pattern rifles and is made from high-quality 9310 and 8620 steel, with both parts being MPI tested for reliability.
This BCG is available with either a Black Nitride or Nickel Boron finish, providing resistance to wear and self-lubrication, respectively.
It is designed with features such as forward assist notches and a staked gas key, and comes fully assembled with all necessary components, including the firing pin and extractor.

Description

Attributes

Cartridge: 308 Winchester Finish: Black Nitride Make: AR .308 Delivery weight: 0.558kg

Item details

Made in USA
US export classification: 0A501.c

Product no.: 078000392
BROWNELLS 308AR BOLT CARRIER GROUP 308 WIN NICKEL BORON MP
Mfr Part: AZT-A10-308-ST- 050806112391 The Brownells Complete .308 Bolt Carrier Group is designed to operate reliably in DPMS LR-308 pattern rifles chambered in .308, .243, 7mm-08, .338 Federal, .260 Remington, 6.5mm Creedmoor, or any other cartridge based on the .308 Winchester. These BCGs are manufactured to the same uncompromising standards as our M16-style BCGs. Our Complete .308 Bolt Carrier Group has a bolt machined from robust 9310 steel, heat-treated and shot-peened for superb hardness. The carrier itself is fabricated from hardened 8620 steel. Both are magnetic particle inspected (MPI) to make sure there are no hidden microscopic flaws that could lead to premature failure. Carrier has forward assist notches Extractor is installed with rubber insert and spring Gas key screws are torqued and staked For use in DPMS LR-308 pattern upper receivers only; NOT compatible with Armalite rifles You can get the Brownells Complete .308 Bolt Carrier Group with a hard Black Nitride finish that is exceptionally resistant to surface wear OR a Nickel Boron coating (a dull matte silver) that’s even harder and self-lubricating to boot. Both come complete with firing pin, firing pin retaining pin, cam pin, gas rings, gas key, extractor, and ejector installed. Brownells GunTech™ Note: Unlike BCGs with a traditional Parkerized finish, the carrier on our Black Nitride bolt carrier group is not hard-chromed inside because Nitride is actually harder than industrial chrome plating.

254.9 GBP 146 £254.90 *

Is a 'Call to order' product.

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Specs: Cartridge: 308 Winchester Finish: Nickel-Boron Make: AR .308

Add to shopping list

Ask question

Details

Add to shopping list

Ask question

🔥 Upgrade your AR .308 with the reliable Brownells 308AR BCG! 🎯 Featuring a Nitride finish, MPI-tested for quality, and compatible with DPMS LR-308. Learn more! ✨

Description
Ratings (13)

The Ideal Big-Bore Bolt Carrier Group

More...

Customer ratings for BROWNELLS 308AR BOLT CARRIER GROUP 308 WIN NITRIDE MP

Number of ratings: 13
From brownells.com: 13
Average rating: 4.5

Great BCG (09/03/2018)

Impeccable quality and unbeatable price (25/03/2018)

Dimensions Wrong Affecting Headspace (06/04/2018)

Nice Bolt but needs some TLC (11/04/2018)

Decent for the money (17/04/2018)

Quality product (07/05/2018)

Runs great in DPMS Pattern 308 AR (01/09/2018)

Awesome (20/06/2017)

Excellent! (09/09/2017)

Awesome, must have (17/12/2017)

Runs great (02/01/2018)

Runs flawlessly in my PSA10 gen 2. Itâs runs smooother than the original bolt Carr group.

Fine Looking BCG (28/07/2018)

Good Looking BCG, packaged good and shipped quick, I was glad to see a JP style firing pin retaining pin on this BCG, GOOD Value on the sale price...

Awesome 308 BCG (11/09/2018)

Wow! Just wow! Purchased for use in an Aero Precision M5 build. Finish is flawless. Cycle smoothly. Every bit as nice as a genuine Aer BCG, but at a much better price. Don't think twice, just buy it.

Read 13 more ratings on brownells.com

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