Sons of Liberty Gun Works 5.56 M16 / AR-15 Bolt Carrier Group - Phosphate

37 Reviews

In Stock

Standard orders will ship out in 1 business days or less if ordered by 3:30 pm CST, Monday-Friday. FFL orders will ship within 5 business days or less as long as we have the information for the transfer destination. NFA items will take longer to ship and are dependent upon ATF processing times.

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If you are looking to build an AR-15 for hard use, to standards that exceed Mil-Spec expectations, then look no further than Sons of Liberty Gun Works. Every component of this bolt carrier group has been properly heat treated and is designed for reliability and longevity. The carrier is machined from AISI 8620 aircraft quality steel and features a full auto profile with durable manganese phosphate coating. The bolt is made from Carpenter Technology No. 158 Alloy and has been magnetic particle inspected as well as high pressure tested to ensure that it will run for many years to come. Every part on a BCG has a specific function and must be made to the highest standards so it doesn’t fail. The gas key is made from 4130 chromoly steel and has grade eight properly staked hex screws to prevent it from coming loose over time. This SOLGW bolt carrier group is a great choice if you are building or upgrading an AR-15.

  • Manganese phosphate finish for corrosion resistance
  • HPT and MPI
  • Hard chromed bore and gas key
  • Carpenter Technology 158 alloy bolt (shot peened)
  • 4340 Tool steel extractor (shot peened)
  • S7 Tool steel ejector (shot peened)
  • Full auto profile 8620 alloy carrier
  • 4130 Chromoly gas key with staked hex screws
  • 4340 Chromoly cam pin
  • 8640 steel alloy firing pin with chrome plating

The Sons of Liberty Gun Works AR-15 BCG comes with many advantages like shot peening to help improve strength and even features small improvements like a precision ground gas key interface on the carrier to help secure the gas key in place. Even the cam pin has subtle improvements like a solid film lubricant that helps reduce wear when the bolt is unlocking. The firing pin is hard chrome plated to prevent breakage. This Complete bolt carrier assembly will ensure that your AR-15 will run reliably for many years to come.

Sons of Liberty Gun Works is a custom rifle manufacturer in the United States that specializes on the AR-15 platform. They began producing purpose-built weapons for law enforcement and civilians alike and are given a lot of praise for focusing on the details that make an AR reliable. Function over form is what their rifles are known for and they are guaranteed to get the job done. From full rifles to individual parts, you can’t go wrong with SOLGW.
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Bolt FinishManganese Phosphate
Bolt MaterialCarpenter 158 Steel
BrandSons of Liberty Gun Works
Caliber Gauge5.56 NATO
Carrier FinishManganese Phosphate
Carrier Material8620 Carpenter Steel
Carrier StyleM16 Bolt Carrier
High Pressure TestedHigh Pressure Tested
Magnetic Particle InspectMagnetic Particle Inspected
Weight11.4 Oz
California Prop 65 warning

 WARNING: This product can expose you to chemicals, which are known to the State of California to cause Cancer and Reproductive Harm. For more information go to

Ratings & Reviews

37 reviews

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Don’t hesitate, just buy it.

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Buy it already. great BCG, great competition, great warranty.

Great BCG


I bought my first one on recommendation from a fellow LEO friend that lives in Texas. Since then I’ve been so impressed that now there are in all my rifles. I took a 5 day course and fired around 1500 rounds during the time and never had an issue, it just ran no matter how dirty or dry it became. When I cleaned and inspected it later it was obvious how well it held up, even the finish. There is nothing overly fancy about this BCG, other than it just works, now I recommend them to everyone I know.

Excellent BCG


So far so good. Seems to be of exceptional quality.


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I have had nothing but Excellent experience purchasing from Primary Arms. FAST shipping, fair prices. Only advise is DO NOT use UPS shipping. Believe it or not United States Postal Service has much faster delivery, at least for me in Los Angeles.

Don’t think twice - if it’s in stock, buy it.


Quality product from SOLGW. And an unbeatable warranty. Customer for life.
<br>Additionally, PA had it at my door 4 days after I purchased.

What else can I say?

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It's a Sons of Liberty Gun Works BCG. Darn thing is a tank. The best BCG I have and I have run the heck out of it. Just keeps asking for more abuse. Wish I would have bought 3 more before the panic buying of 2020 drop-kicked the gun industry.

Great BCG

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Best BCG for your buck. This is my 4th sons bcg. No issues with the first 3. Not only that but when my bcg was stolen out of my shipment by the delivery driver, primary arms replaced it when they got their next shipment.


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Sons Of Liberty Gun Works have certainly earned their place in the firearm industry by producing excellent quality products that people can trust and rely on when it counts. I would easily rank this BCG up there with other duty/battle grade weaponry from other industry leading firearm companies. Quality control standards and bomb proof gear, SOLGW offers a LIFETIME warranty on any and ALL of their products in the event of a problem or failure they will without question take care of their customers. There are soo many choices nowadays but rest assured... if you purchase anything from SOLGW you will not be sorry and you can rest easy knowing your equipment is GTG!! As always Primary Arms absolutely rocks and got this item within 3 days during the holiday season! With companies like Primary Arms its almost hard to see the point in paying other online retailers that require a "subscription".. One things for certain, Ill be a lifelong customer of PA!!

Best BCG on the market!

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After some extensive research and usage of other bolt carrier groups on the market, I have landed on this one. It’s built to an extremely high level of quality. Fit and finish are perfect and it functions just as well. The guys at SOLGW know what they’re doing. Building components without frills. Their parts are built to be used, and used hard.

SOLGW 5.56 BCG - A solid purchase at a fair price!

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I was on the Primary Arms wait list when this product came available. Reliable delivery, fair price, good fit and very dependable function. I would refer this product to a friend.
<br>Thank you-