Expo Arms 5.56 NATO Complete M16-Cut AR-15 Bolt Carrier Group - Nitride

Manufactured by Expo Arms
Manufactured by Expo Arms
7 Reviews

In Stock

Standard orders will ship out 1 business day 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.

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The Expo Arms Bolt Carrier Group is a great choice for any build. This drop-in AR-15 BCG features a corrosion resistant salt bath nitride finish, MIL-SPEC dimensions, and a magnetic particle inspected carpenter 158 steel bolt. Crafted from domestically sourced 8620 steel, the M16 cut carrier includes a gas key fastened by properly staked grade 8 screws. Made in the U.S.A. and covered by a lifetime warranty, you can count on this BCG for a lifetime of service.

  • .233/5.56 NATO
  • Salt bath nitride finish
  • M16 cut
  • Aircraft quality 8620 steel carrier
  • 4130 steel gas key
  • Properly staked grade 8 gas key screws
  • Carpenter 158 steel bolt
  • 4140 steel extractor
  • MIL-SPEC O-ring
  • MIL-SPEC gas rings
  • 4140 steel cam pin
  • 8740 steel firing pin with hard chrome finish
  • Magnetic particle inspected
  • Lifetime warranty
  • Proudly made in the U.S.A.
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Bolt FinishSalt Bath Nitride
Bolt MaterialCarpenter 158 Steel
BrandExpo Arms
Caliber Gauge5.56 NATO
Carrier FinishSalt Bath Nitride
Carrier Material8620 Carpenter Steel
Carrier StyleM16 Bolt Carrier
High Pressure TestedHigh Pressure Tested
Magnetic Particle InspectMagnetic Particle Inspected

WARNING: This Product can expose you to chemicals which is known to state of California to cause Cancer and Reproductive Harm. For more information, see www.p65warnings.ca.gov

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 www.P65Warnings.ca.gov.

Ratings & Reviews

7 reviews

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Awsome sales experience and great product

by -

This item was an add on option to the Bear Creek Arsenal 16" Mlok 300 AAC Blackout upper assembly I purchased to add functionality to my home built 5.56mm AR. This is a melonited (Nitrided) BCG. After a day at the range, I came home and cleaned the upper. The melonite finish makes cleaning a very easy task. This BCG functioned flawlessly. I'm really impressed with the speed that Primary Arms had the upper with options delivered on my doorstep only 3 days after I ordered it.Great product at a great price. Thanks Primary Arms!

I'm happy.

by -

Will update if I have any issues but upon initial inspection this is a very nice BCG. Mine has absolutely no tool maks, the nitride is smooth and looks really nice. BCG is in spec compared to other BCG's I have. I'm happy with this purchase.


by -

Updating my review. I've had this for about 7 months as of 3/06/19. I have about 800 rounds cycled so far with this BCG and I have not had a single malfunction. This is paired with the Bear Creek 7.5 inch nitrided barrel. Again... the machining and finish are perfect. Been recommending this BCG to everyone. Unless you want something really fancy or gotta have a specific logo, I see no benefit in spending more on other brand names when you get the same quality for less.


by -

Everything you would expect from a $200 BCG for less than $100. Over 200 rounds on the first day and zero issues. Will update if it performs less than expected, but I don't foresee any issues.

Good bang for your buck


5k rounds and still strong. Had an extractor shatter but thats not an issue.

Great BCG


Amazing BCG for $100. Build quality is great and works flawlessly. Would definitely recommend this BCG to anyone.

Works Great


This is a steal. It works well and is perfect for both Wylde and Nato. Quick shipping as always!