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Ar-15 Pro Series Bolt Carrier Group 5.56mm - Pro Series 5.56 Bcg 9310 Steel Bolt Black Nitride For Ar-15
Our editorial team reviews specifications, product data, and field-use information to keep pages accurate.
$172.99
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SKU: 100044026
Overview
Built for an AR-15 in 5.56mm, this bolt carrier group is aimed at shooters who want a duty-oriented component for hard use and demanding conditions. Aero Precision’s PRO Series focuses on service life, with each part and process selected to support dependable operation over time. The package includes a firing pin ground from 8640 steel, a gas key machined from hardened 4140 steel and staked to Mil-Spec, and a cam pin machined from 4140 steel with an engraved indexing mark. Its nitride finish across key components gives it a clean, purpose-driven presentation without adding unnecessary complexity.
Why Hunters Choose the Aero Precision
Aero Precision
PRO Series 5.56 Bolt Carrier
Gas Key
Grade 8 hex fasteners
Gas Key
Is properly staked to Mil-Spec
Firing Pin
Is ground from 8640 steel
Cam Pin
Is precision ground after heat
Key Features
- Aero Precision PRO Series 5.56 Bolt Carrier Group for AR-15 platforms
- Built to meet the demands of extreme conditions
- Designed to increase reliable service life of the bolt carrier group and its components
- Firing pin ground from 8640 steel with nitride finish
- Gas key machined from hardened 4140 steel, torqued to spec, and properly staked to Mil-Spec
- Cam pin machined from 4140 steel, precision ground after heat treatment, with engraved indexing mark
Best Used For
- Hunters building an AR-15 for demanding field use and consistent operation
- Shooters wanting a PRO Series bolt carrier group with specified component materials
- Users who prefer a Mil-Spec staked gas key and nitride-finished parts
- AR-15 owners replacing a bolt carrier group with Aero Precision components
- Those seeking a 5.56 BCG for hard-use setups without extra feature claims
Specifications
| Cam Pin Finish | Nitride Finish |
|---|---|
| Cam Pin Marking | Engraved Indexing Mark |
| Cam Pin Material | 4140 Steel |
| Firing Pin Finish | Nitride Finish |
| Firing Pin Material | 8640 Steel |
| Gas Key Fasteners | Grade 8 Hex Fasteners |
| Gas Key Finish | Nitride Finish |
| Gas Key Material | Hardened 4140 Steel |
| Gas Key Staking | Properly Staked to Mil-Spec |
| Manufacturing Process | Precision ground after heat treatment |
Pros
- Aero Precision PRO Series 5.56 Bolt Carrier Group designed for demanding conditions
- Gas key is torqued to spec with grade 8 hex fasteners
- Gas key is properly staked to Mil-Spec for secure assembly
- Firing pin is ground from 8640 steel with nitride finish
- Cam pin is precision ground after heat treatment
- Includes an engraved indexing mark on the cam pin
Considerations & Trade-offs
- The PRO Series BCG is positioned for demanding use, but the provided details do not include specific performance metrics or test data, so suitability for a given setup should be evaluated against the rifle’s intended role.
- Several components are nitride finished, which is a design choice to note, but the listing does not provide maintenance requirements or long-term wear expectations beyond the stated materials and finishes.
- The description emphasizes service life and extreme conditions, yet it does not specify compatibility details beyond 5.56mm, so buyers should confirm fitment for their exact AR-15 configuration.
- At $172.99, this is a premium-priced component; the value depends on whether the listed material and assembly details align with the level of build quality you want.
Suggested Comparisons
- AR-15 bolt carrier groups
- AR-15 upper receiver components
- 5.56mm rifle parts
- AR-15 maintenance and replacement parts
Suggested Accessories
- AR-15 cleaning kit
- Spare bolt carrier group parts
- Gun lubricant
- Upper receiver maintenance tools
Frequently Asked Questions
What is included in the Aero Precision PRO Series 5.56 Bolt Carrier Group description?
The provided data identifies it as a PRO Series 5.56 Bolt Carrier Group for AR-15 use. The listed components in the description include a firing pin, gas key, and cam pin, with material and finish details provided for those parts.
What materials are specified for the firing pin, gas key, and cam pin?
The firing pin is ground from 8640 steel, the gas key is machined from hardened 4140 steel, and the cam pin is machined from 4140 steel.
What finish is listed for the parts in this bolt carrier group?
The firing pin, gas key, and cam pin are all listed with a nitride finish.
Does the product information mention how the gas key is secured?
Yes. The gas key is described as torqued to spec with grade 8 hex fasteners and properly staked to Mil-Spec.
Is there any information about compatibility beyond 5.56mm AR-15 use?
The product title and description identify it as a 5.56mm bolt carrier group for AR-15 use. No additional compatibility details are provided in the supplied data.