Expo Arms 5.56 NATO Complete MIL-SPEC M16 / AR-15 Bolt Carrier Group - Chrome

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.

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.

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.

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


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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!

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.

Used it in my older rifle an runs better than ever

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.

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.

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.