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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 Price: $69.95
Savings: $80.04


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

Average Rating: 5 of 5 Total Reviews: 7 Write a review »

  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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  0 of 0 people found the following review helpful:
Not much to say March 1, 2019
Reviewer: John from Sanford, NC United States  
It's quality and runs great.  Shipping was very fast

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  0 of 0 people found the following review helpful:
Best price on MPI/HPT bolt March 1, 2019
Reviewer: Bobby from TN  
Great HPT BCG.  I haven't been able to find another true mil spec bolt carrier group at this price point.  They're not as pretty as some other carriers but i'll take the reliability of an HPT bolt all day

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  3 of 3 people found the following review helpful:
AO is My New Favorite BCG April 10, 2018
Reviewer: Binary Beast Mode from RICHMOND, TX United States  
I ran this bolt with my Franklin Armory BFS3 and it worked like a champ. Me and my buddy first ran about 100rnds in semiauto, the we ran another 100rnds in binary mode just double tapping. Once we got my FN CHF Barrel good and hot, then we went "FullSemi Auto" LOL. We ran 300rds Full "binary mode" aka poormans FullyAuto. So a total of 500rnds and we did n'\ot have 1 failure of any kind. AO Precision BCG did not fail with that abuse. I will be buying much more

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