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AO Precision Premium Phosphate Bolt Carrier Group - 158 HPT/MPI

AO Precision 158 HPT/MPI Mil-Spec Phosphate Bolt Carrier Group

MSRP $149.99
Deal of the day: $79.95
Savings: $70.04


Stock Status :IN STOCK
Product Code: AOM16-HPT-MPI

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AO Precision Premium Mil-Spec Phosphate Bolt Carrier Group - 158 HPT/MPI BCG

These Military surplus 158 Bolt carrier groups are manufactured by AO Precision to the exacting standards of the US Military. AO makes these HPT / MPI BCG's for other Military contractor juggernauts, such as FN America. All bolts are rigorously inspected and are individually High Pressure Tested and then go through a Magnetic Particle Inspection.

Mil Spec Bolt
  • 158 Carpenter Steel
  • Shot Peened
  • High Pressure Tested (HPT)
  • Magnetic Particle Inspected (MPI)

Mil Spec Carrier
  • 8620 Aircraft Grade Steel
  • Full Mass M-16

Mil Spec Extractor
  • 4140 Steel per ASTM A108, cold drawn and stress relieved BHN 187-22
  • Phosphate Finish
  • Extractor Spring
  • Black Extractor Insert
  • Viton O-Ring

Mil Spec Gas Key
  • 4130 Profile Extruded Steel
  • Grade 8 Hardware
  • Properly Staked
  • Chrome Interior

Please note: These BCG's are considered premium because of the materials used and the Military Spec requirements that are adhered to during the manufacturing process. The HPT/metallurgy equipment and processes that these go through are very hard to find and very expensive. These are battle proven (literally), but they may not be as pretty as other BCG's out there.

Average Rating: 5 of 5 Total Reviews: 10 Write a review »

  0 of 0 people found the following review helpful:
July 10, 2019
Reviewer: Phillip Giles from Land o lakes, FL United States  

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  0 of 0 people found the following review helpful:
Great Mil Spec BCG June 24, 2019
Reviewer: Justin from Illinois  
If you like phosphate and chrome lined BCG's, you will like these. Beautifully smooth phosphate finish, C158 HPT/MPI Bolt, and good staking on the gas key. I bought 4 of these because they're too good a deal to pass up. They look better than other C158 phosphate/chrome BCG's I've seen in this price range.

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  0 of 0 people found the following review helpful:
Top Quality April 29, 2019
Reviewer: Ivan from IL  
All I can say is that the stalking are perfect very deep both sides. Much better than my Spikes tactical bcg. No AO Logo which is fine for me and priced well. Fast Shipping was a Plus.

Thank you RTB!

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  0 of 0 people found the following review helpful:
Excellent BCG April 5, 2019
Reviewer: Anthony Martinez from TUCSON, AZ United States  
Fantastic BCG. One indicator on a great bolt carrier is the quality of the staking. The staking is deep with material biting right into the bolts. The chrome lining in the carrier is uniform and free of any tooling marks from front to aft. The outside has absolutely no tooling marks, and the phosphate coating is very smooth and uniform. The bolt itself is marked HPT/MPI. The extractor spring seems a tad weak, even compared to other stock extractor springs I pulled from other brand BCGs. The cam pin fits tight into the cam pin hole in the bolt with little play side to side. More than any other BCG's I've had. In all honesty, this looks better than my BCM parkerized BCG I bought a year ago, and at less than half the price. I'd rate it higher than 5 stars if I could.

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  1 of 1 people found the following review helpful:
Only BCG I'll buy March 1, 2019
Reviewer: Anonymous Gross from GODDARD, KS United States  
For the cost you can't get a more reliable bolt carrier

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