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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
SALE PRICE: $129.99
Savings: $20.00


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: Average Rating: 5 of 5 5 of 5 Total Reviews: 19 Write a review »

  1 of 1 people found the following review helpful:
5 of 5 One small detail I LOVE! August 28, 2020
Reviewer: MrBang from Riddle, Oregon, USA  
This is an excellent bolt carrier group.  Well staked, good chrome lining.  All the fun initials like MPI and stuff on it.  But the ONE thing I really love about it?  It has a PROPER firing pin retaining pin.  If you've never seen one before, you are missing out.  Colt guns have the proper pin.  It is ground to a conical point for super easy reinsertion and the head is flattened so it doesn't stick out of the carrier and drag on the inside of your aluminum receiver.  SO MUCH BETTER than the hardware store cotter pins that look like they were cut to length with dull wire cutters.  This is the first aftermarket BCG I've ever seen that came with a real quality pin.  As long as RightToBear has these in stock I'm not buying anything else!

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  1 of 1 people found the following review helpful:
5 of 5 Looks good! March 22, 2020
Reviewer: Jon from Ohio  
Everything looks good. Staking is good, machining quality is good, chrome lining looks good.

Cleaned it, oiled it and slapped it into one of my rifles. No open gun ranges around due to Wuhan Virus. I will wait patiently.

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  1 of 1 people found the following review helpful:
5 of 5 Bolt Worked March 9, 2020
Reviewer: Jack from Texas  
It came a little tight, the bolt would hardly move inside the carrier. After 120 rounds it moves great and i can flick it open now. Didn't fail at all after rocking through the ammo fast. I dig it.

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  0 of 0 people found the following review helpful:
5 of 5 Great product February 13, 2020
Reviewer: Brandon Wilson from Deridder, LA United States  
These are the best you can buy at these prices, bar none.

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  2 of 2 people found the following review helpful:
5 of 5 Advanced Ordnance parts January 26, 2020
Reviewer: Robert from Florida  
Managed DoD contracts years ago, and had AO as an assignment.  Bolts for M-16s and 20mm bolts for Vulcan gatling guns were made there.  Quality good enough for the Pentagon and for me as well...

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