What is BCG? 🔔
It is a component of a firearm, responsible for extracting spent casings, loading fresh rounds, and ensuring the safe and reliable operation of the rifle. It consists of the bolt, bolt carrier, gas key, firing pin, and extractor.
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Parts 🧩
| 🔩 Bolt: | The bolt is the part that locks into the barrel extension and chambers the round. |
| 🚂 Bolt Carrier: | The bolt carrier houses the bolt and moves back and forth during the cycling of the firearm. |
| 🔑 Gas Key: | The gas key is attached to the bolt carrier and receives the high-pressure gas from the gas tube to drive the bolt carrier backward. |
| 🔨 Firing Pin: | The firing pin strikes the primer of the cartridge, igniting the propellant and firing the round. |
| 🔧 Extractor: | The extractor grips the rim of the spent casing and pulls it out of the chamber during the extraction process. |
Functions ⌛
| Cycling: | It facilitates the cycling of the firearm by moving back and forth during each firing cycle. It extracts and ejects the spent casing and loads a fresh round from the magazine into the chamber. |
| Chambering: | The bolt locks into the barrel extension, ensuring proper alignment and chambering of the round. |
| Firing: | The firing pin strikes the primer of the cartridge, initiating the ignition process and firing the round. |
| Extraction: | The extractor grips the rim of the spent casing and pulls it out of the chamber during the extraction process. |
| Gas Operation: | In gas-operated firearms, the bolt carrier group receives high-pressure gas from the gas tube through the gas key, driving the BCG backward and initiating the cycling process. |
Types 🔊
🏢 Standard Bolt Carrier Group: This is the most common type, typically used in rifles chambered in standard calibers like 5.56mm or .223 Remington. It features a standard weight and design.
🗜️ Lightweight Bolt Carrier Group: They are designed to reduce overall weight and improve the rifle’s handling characteristics. They usually feature weight-reducing cuts or materials without sacrificing reliability.
🎣 Enhanced Bolt Carrier Group: Enhanced items often come with additional features or modifications to improve performance and reliability. They may have enhanced extractors, enlarged ports for better gas flow, or upgraded coatings for increased durability.
🖤 Nickel Boron Bolt Carrier Group: Nickel Boron-coated items have a durable and self-lubricating coating, offering increased corrosion resistance, reduced friction, and ease of cleaning.
Bolt Carrier Group Review | Best Nickel Boron BCG
| Image | Product | Brand | |
|---|---|---|---|
 | Aero Precision .308 Black Nitride | Aero Precision |  |
| ODIN Works Nitride Bolt Carrier Group, Black | ODIN Works | |
 | FosTech Outdoors AR-15 Complete Bolt Carrier Group | FosTech | |
 | Spikes Tactical M16 Bolt Carrier Group | Spikes Tactical | |
 | RISE Armament AR-15 Bolt Carrier Group | RISE Armament | |
 | FosTech Outdoors AR-15 Complete Lite Bolt Carrier Group, Low Mass | FosTech Outdoors | |
 | JP Enterprises Complete JPBC Bolt Carrier Group | Bolt Carrier Group | |
 | Aero Precision AR15 5.56 Bolt Carrier Group | Aero Precision | |
 | ODIN Works Bolt Carrier | ODIN Works | |
 | FailZero M16/M4 Bolt Carrier Group, No Hammer | FailZero | |
 | TRYBE Defense Milspec Complete 9mm Hybrid Bolt Carrier Group | TRYBE Defense | |
 | Ballistic Advantage .308 Bolt Carrier Group | Ballistic Advantage | |
 | Alpha Shooting Sports ALPHA Premium 5.56 Nitride V2 Bolt Carrier Group | ALPHA | |
 | FailZero AR15 Bolt Carrier Group w/ Hammer | FailZero | |
 | Midwest Industries 5.56/AR15 C158 Bolt Carrier Group | Midwest Industries | |
1# Aero Precision .308 BCG (Black Nitride)
The first model we are going to review is a good but rather expensive solution for big-bore builds. This .308/7.72 BCG is made of case-hardened 8620 steel, and it’s also high-pressure tested and magnetic particle inspected. Thanks to high-quality coating and solid elements, you can enjoy a long-lasting and smooth experience. The carrier has forward assist serrations for better performance.
2# ODIN Works Nitride BCG Black
For a lower price, you can find this interesting model. A bolt carrier group made of Case Hardened 8620 Steel with nitride finish that is compatible with mil-spec uppers. An attached Grade 8 hardware 4130 steel gas key and high-pressure tested bolt together with an O-ring compatible extractor and mil-spec firing pin allows you to feel what the real shooting is. So don’t miss this device if you see it on the market.
3# FosTech Outdoors AR-15 Complete BCG
If you need a full-auto BCG compatible with Echo AR-II and the Echo Sport, this model is a good purchase. Good balance, affordable price, and durable materials — this is what you want to see in a bolt carrier group for your AR-15 rifle. Based on our experience nickel-boron coating reduces the need for lubricants and ensures corrosion resistance, so you don’t have to worry about the lifetime.
4# Spikes Tactical M16 BCG
One more full-auto M16 BCG made of mil-spec 8620 tool steel that offers good characteristics for a quite standard but yet not cheap price. All elements are high-pressure tested and MPI marked. The bolt is shot-peened, and the carrier key is firmly attached to Grade 8 hardware. The O-ring on the extractor facilitates installation and use. It’s a reliable model that is totally worth buying if you need such parameters.
5# RISE Armament AR-15 BCG
A nice, durable, and well-tested bolt carrier group for 5.56x45mm NATO, .223 Remington calibres can make you satisfied not only with decent characteristics but also with a nice price. A magnetic particle-inspected bolt made of 9310 steel, a heat-treated 8620 tool steel carrier, reduced friction, and smooth operation will make your shooting experience simple and enjoyable. The gas key is staked properly, and the extractor is shot-peened.
6# FosTech Outdoors AR-15 Complete Lite BCG
What have we got here? This is a low-mass bolt carrier group that is designed for 5.56/.223. calibre and it has some peculiarities. First of all, it’s really lightweight, and it’s only 8.6oz. Due to such sizes, this model is not mil-spec compatible. The finish is one of the strongest advantages of the BCG. If you want to make a lightweight but solid and reliable build with no glitches and snags, it’s a perfect solution. However, it will cost you some money, so be ready for it.
7# JP Enterprises Complete JPBC BCG
Talking about lightweight BCGs, we should mention a 9mm bolt carrier group designed by JP Enterprises. It’s one of the most reliable 9mm systems, and it features reduced stroke length, reduced bolt bounce, and a tighter firing pin channel. Our findings show that thanks to these elements, the bolt carrier group is very durable but lightweight. The finish here is also good, it increases reliability and allows you to forget about the constant use of lubricants.
8# Aero Precision AR15 5.56 BCG
In the 8th place, we have an M-16-cut bolt carrier group machined from 8620 steel and designed for 5.56x45mm NATO caliber. Despite the low price, this model has a nice range of features that any professional or amateur shooter will like. First of all, materials are solid. Besides, the BCG is shot-peened, high-pressure tested, and magnetic particle tested. The gas key is firmly attached and properly staked. The extractor has an O-ring insert for easier use. In addition to this, forward assist serrations make operation smoother.
9# ODIN Works BCG
Another model by ODIN that makes customers happy for a long time. There is nothing special about this bolt carrier group — it’s all about the perfect balance between the price and characteristics. Here you will find a mil-spec compatible BCG made of case-hardened 8620 steel and coated with a black nitride finish. All details are HPT tested and MPI marked, the operation is smooth and simple. Build an accurate, reliable, and cheap rifle with custom elements like this.
10# FailZero M16/M4 BCG
Regarding this model, it’s a cheap but great solution for 5.56/.223 calibers for M16/M4/AR15 rifles. It’s super easy to install on the majority of mil-spec uppers, and it ensures nice durability thanks to the EXO nickel-boron coating that reduces friction and corrosion. It can be a great add-on for your firearm, so don’t think twice if you can buy it. This will be a good buy.
11# TRYBE Defense Milspec Complete 9mm Hybrid BCG
If you have a 9mm AR-15 carabine, this BCG is what you need. It’s suitable for Colt- and Glock-style lowers and it ensures good durability and smooth, fast operation. This model is made of 8620 steel and has a nitride finish, which means no extra friction while operating and long service life. It has mil-spec dimensions.
12# Ballistic Advantage .308 BCG
Thanks to an 8620 alloy steel carrier and a bolt made of 9310 alloy steel, this 7.62/.308 BCG designed by Ballistic Advantage ensures nice performance and durability. The only downside of this model is, probably, the price because it’s not low. All the characteristics are good, and the features are useful. Except for high-quality elements, this bolt carrier group offers a properly staked gas key, a shot-peened bolt, high-pressure tested and MPI marked details, Viton O-ring, and forward serrations. Those who don’t have budget limits should take a look at this model.
13# Alpha Shooting Sports ALPHA Premium 5.56 Nitride V2 BCG
We know you like inexpensive solutions for your custom builds. Take a look at this model because it has everything you need: an 8620-steel carrier coated with a nitride finish, improved carrier geometry, reduced friction, corrosion resistance, and so on. Although the price is not high, the quality is good. The parts are MPI marked and tested. This is a reliable solution.
14# FailZero AR15 BCG
Previously, we’ve been reviewing the same bolt carrier group but without a hammer. This model has a hammer and offers the same range of features. Basically, it’s a good, balanced, and very durable bolt carrier group that comes with a hammer. The nickel finish makes it even better, ensuring smooth operation and resistance. Improve any semi-auto AR-15 rifle with a good-looking and easy-to-use BCG.
15# Midwest Industries 5.56/AR15 C158 BCG
And the last one is a balanced bolt carrier group that offers good characteristics for a low price. The point that the manufacturer decided to use lighter materials to lower the price and improve other vital parameters. So, the bolt is made of Carpenter 158, and it’s heat-treated, shot-peened, and also MPI Tested. In collaboration with Nickel-Boron coating, this bolt carrier group ensures awesome performance.
Installation 🚨
Ensure the firearm is unloaded and the safety is engaged. Always prioritize safety when working with firearms. Begin by separating the upper and lower receivers of the firearm. If necessary, remove the handguard or any other components that may obstruct access to the Carrier Group.
With the upper receiver exposed, position the bolt carrier group so that the bolt face is aligned with the chamber of the barrel. Slide the bolt carrier group into the upper receiver, ensuring the charging handle aligns with the channel in the Bolt Carrier Group. Push the bolt carrier group fully forward until it locks into place. The forward assist (if present) should engage the bolt carrier.
Next, insert and secure the retaining pin (also known as the cam pin) through the designated hole in the bolt carrier. Rotate the cam pin until it aligns with the slot in the upper receiver. This ensures proper alignment and smooth operation. If your firearm has a gas system, ensure the gas key aligns with the gas tube. Use the appropriate tools to tighten the gas key screws securely.
🔧 Finally, the function checks the Bolt Carrier Group to ensure it moves freely and smoothly within the upper receiver. Cycle the charging handle to verify proper operation. If necessary, clean and lubricate the bolt carrier group following the manufacturer’s recommendations for maintenance.
We believe this video can be helpful for you 📺
FAQ 🛑
Conclusion ⏰
The Bolt Carrier Group is a vital component of a firearm and is responsible for the extraction, ejection, and chambering of rounds. It consists of various parts, including the bolt, bolt carrier, gas key, firing pin, and extractor. Understanding the different types, materials used, finishes available, and proper maintenance procedures ensure the reliable and optimal performance of the firearm. Whether it’s installing, cleaning, or lubricating, following safety guidelines and manufacturer recommendations are essential. Keeping the item in good condition through regular maintenance helps maintain the firearm’s functionality and longevity. 🧩🛒
Tags: #Best #BCG #Nikel Boron #9mm #AR 15 #308 #Coating #Folowing #300 Blackout #Grendel 6.5 #Budget #Lube #Matrix #Review #For The Money #7.62×39 #5.56 #Glock #Nitride #Odin #Aero Precision
Tactical accessories are another passion of mine that I could write about endlessly - my house and garage are full of tactical gadgets, luckily my family shares my interests.
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I absolutely adore my Nickel Boron Rise Armament bolt carrier group (BCG) for its excellent lubrication and effortless upkeep. It surpasses the smoothness of my other BCGs with DLC and Nitride finishes that are installed in my other rifles. With improved finishes, I spend less time cleaning via brushing and wiping, compared to the time taken to clean a traditional phosphate finish.
A trustworthy source who has worked on a lot of ARs mentioned that Nickel Boron could create problems due to its uneven finish. This could cause the bolts to have improper head spacing and become too large. As a result, I recommend choosing one of the nitride finishes or the standard MILSPEC phosphate instead. If you do decide to go with Nickel Boron, it’s important to use a headspace gauge to check it, as this is a good practice to follow for any type of finish.
Hi! Can I upgrade my Bolt Carrier Group?
🟣 Yes, there are various aftermarket upgrades available for Bolt Carrier Groups. These upgrades can include enhanced coatings, lightweight designs, enhanced extractors, and improved gas keys. However, it is important to ensure that any upgrades you choose are compatible with your firearm and comply with applicable laws and regulations.
Thank you for the helpful information. I am in the process of gathering parts for my first AR build, and I have already bought a FailZero NiB BCG. Your experience confirms that even products from the same manufacturer can vary in quality.
I mostly use BCG’s from RCA because I really like them and they are reasonably priced. The company that makes them also manufactures BCGs for Noveske and owns its own metal treatment process.
My BCM rifle has a Lantac installed, and it functions well with useful features for suppressed firing. I haven’t encountered any problems yet, and it is easy to clean.
Thank you for providing me with all the information about the various qualities of steel and finishes available for a BCG. It has been really helpful, especially since I am building my first AR-10 and had no prior knowledge about it.
Hello. Can I install a full-auto Bolt Carrier Group in my semi-auto rifle?
🟨 While it is technically possible to install a full-auto Bolt Carrier Group in a semi-auto rifle, it is illegal in many jurisdictions. The possession or installation of a full-auto BCG in a semi-automatic firearm without proper licensing and compliance with applicable laws can result in serious legal consequences.