Expo Arms 5.56 NATO Complete MIL-SPEC M16 / AR-15 Bolt Carrier Group - Chrome
Details
Details
The Expo Arms 5.56 NATO Complete MIL-SPEC M16/AR-15 Bolt Carrier Group is a reliable and high-quality option for any build. This drop-in bolt carrier group (BCG) is specifically designed for AR-15 platform firearms chambered in .223/5.56 NATO.
Featuring a hard chrome finish, this BCG provides exceptional corrosion resistance, ensuring durability and longevity. The MIL-SPEC dimensions guarantee compatibility with a wide range of AR-15 platforms. The bolt is constructed from magnetic particle inspected Carpenter 158 steel, known for its strength and reliability. The carrier is crafted from aircraft-quality 8620 steel and features the M16 cut. It includes a gas key secured by properly staked grade 8 screws for enhanced reliability. The gas key is built from 4130 steel to withstand the demands of consistent firing.
Additional features of this Expo Arms BCG include a 4140 steel extractor, MIL-SPEC O-ring and gas rings, 4140 steel cam pin, and a hard chrome-finished 8740 steel firing pin. These components are carefully chosen for their durability and functionality. Expo Arms takes pride in manufacturing this BCG in the U.S.A., utilizing domestically sourced materials.
Features:
- Chambered in .233/5.56 NATO
- Hard chrome finish for corrosion resistance
- M16 cut for reliable performance
- Aircraft-quality 8620 steel carrier
- 4130 steel gas key with properly staked grade 8 screws
- Carpenter 158 steel bolt for strength and reliability
- 4140 steel extractor
- MIL-SPEC O-ring and gas rings
- 4140 steel cam pin
- Hard chrome-finished 8740 steel firing pin
- Magnetic particle inspected for quality assurance
- Lifetime warranty
- Proudly made in the U.S.A.
Specifications
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
22 reviews
Best BCG for the money
by Wolfgar
The Chrome is well done and everything is in spec. I actually have the gauges to gauge my BCG's and the chrome expo Arms I have gauged have been top notch. The 3 bores, bolt face, bolt tail to bolt tail bore interface tolerance, carrier length, gas key I.D./straightness/staking, firing pin protrusion, bolt support shoulder, machining, bolt face, etc all passed with flying colors.
Expo Chrome BCG
by Dino
Not much for words, I have 4, one in my main rifle been using it for a year or so. Two month ago I had to replace the rings, other than that perfect. Recommended.
Solid
by IndependentArmz
These are well built bcg groups. They are staked nice, with tight rings and well finished chrome. I did have head spacing issues in several barrels. All FN CHF. One 10.5 and a 14.5. It did space out well in aero barrels and some other. Still very happy with the quality and price on these. Would buy more.
Out of spec
by Brent Kummer -
I was initially impressed with it until I tried running it. Either the bolt, carrier, or gas rings is out of spec. Haven’t dug into yet. The gun would cycle, but the bcg wouldn’t lock back. The bolt itself will move in the carrier unless a bunch of pressure is applied. We swapped it out for a solgw bcg at the range and the gun ran great
Thank you for taking the time to share your feedback. We sincerely apologize that your recent experience with Primary Arms fell short of your expectations. We value your loyalty as a long-term customer and regret any frustration caused by the issue you encountered.
We strive to provide exceptional customer service and resolve all concerns efficiently. We'd appreciate it if you could share more details about the specific issue you faced. This information will help us investigate further and improve our processes to prevent similar situations.
We're committed to regaining your trust. If you'd be open to it, we'd like to discuss potential solutions and see if we can find a way to earn back your business.
Please feel free to email us at info@primaryarms.com Attention CS manager or call us directly at 713-344-9600 (please advise the agent you are returning the manager's call) to discuss this further.
GREAT BCG!
by Jacob -
I was interested in this being it's claimed to be a Microbest and it was on sale. After seeing some reviews about the quality control on them including sharp edges, burs, etc., I was skeptical on purchasing but this BCG came in flawless and smooth. Couldn't be happier!
Expo Chrome BCG.
by Kc MCD -
I got the expo arms chrome BCG on sale. It looks great, and functions great. Clean up is extremely easy. Being that I got it on sale, I would say it's the best BCG at that price point.
Great BCG
by Avery -
Used it in my older rifle an runs better than ever
Quality is hit-and-miss
by Harold -
I ordered two of these at the same time. The first one was excellent in quality. Smooth finish, great tolerances, good head space, and gauged nicely.
The second one was a different story. It had some nicks and sharp edges on the rails (I stoned those a little to smooth them out), and the ejector was so tight I had to use pliers to remove it from the bolt -- this is a reliability issue. So I had to install a new ejector.
So in short, if you get a good one, you'll be very happy. But the quality is inconsistent from unit to unit, so be wary and inspect it carefully before installation.
Good value and well made!
by Jeff
Seems to be really well made and a good value for the price. PA customer service stated to me that the bolts are individually HP tested and MPI.
Seems to have smooth well fit bores and the bolt feels smooth with slid in and out by hand.
I will absolutely buy another without hesitation.
From Microbest
by Addison -
I hear these are made by the subcontractor microbest. That company is know for such BCGs as BCM, Daniel Defense, Colt, and FN. So you are getting their BCG for cheaper and with a superior coating.