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A Toolcraft Nickel Boron BCG is, hands down, one of the best Nickel Boron BCGs (NiB BCG) on the market today. The bolt carrier group is one of the most important AR15 parts, critical to the safety and proper function of the AR15. Toolcraft understands this and precision manufactures these bolt carrier groups on state-of-the-art CNC machinery in North Carolina to such high standards that they are trusted by the U.S. Military and carry a lifetime warranty.
Nickel Boron is an extremely durable finish with self-lubricating properties so your AR15 cycles smoother and requires less lubrication. Toolcraft has the Nickel Boron finish applied by UCT Coatings of Palm City FL, the same company that applies it for Fail Zero BCGs. Called EXO Technology, this is a patented process that applies a Nickel Boron finish so durable that it is specified on Army 81mm and 60mm mortar tubes, Blackhawk helicopter hoists, and for hard use applications on some Navy ships! IMO, this may be the ultimate upgrade to the All-American AR-15. And it looks good too!
See our blog article Top 3 Reasons You Might Want a Nickel Boron BCG
Explore different finishes here AR15 BCG Finishes
A bolt carrier group is only as good as it’s bolt. Choose from either the very popular 9310 steel or the mil-spec 158 Carpenter steel. Both are modern ultra-high strength steels designed specifically for applications where high strength and durability are of paramount importance.
This is a 223/5.56/300 Blackout bolt carrier group.
This AR BCG will not work with 6.5/6.8/308 etc.
|Bolt||Shot Peened; MPI|
|Bolt Material||9310 or Carpenter 158 Steel|
|Bolt Finish||Nickel Boron|
|Extractor O-ring||Viton; Mil Spec|
|Carrier Material||8620 Steel|
|Carrier Finish||Nickel Boron|
|Carrier Design||M16 Full Auto Style|
|Gas Key Material||4130 Steel|
|Cam Pin Material||4140 Steel|
|Cam Pin Finish||Nickel Boron|
|Firing Pin Material||8740 Steel; Hard Chrome Plated|
Toolcraft products carry a lifetime warranty. Simply put - should any of our products fail, return it to us for a brand new replacement.
A note from Toolcraft
Toolcraft carriers are made from the best materials that can be purchased in the market today. Regardless of the coating you choose, the carrier that it protects is made the right way, with no compromise of standards using materials that are Made in the USA. There is the basic 8620 steel, a better grade of Gun Quality 8620 steel, an even better grade of Aircraft Quality 8620 steel, but then there is the best Aircraft Quality 8620 steel that is proprietary to Toolcraft only and no one else. These high standards of materials set us apart from the rest.
While some manufacturers have compromised the Mil-Spec standards of machining just to add to their profits, Toolcraft has stayed loyal to the Mil-Spec machining standards since the beginning.
All Toolcraft carriers are post-heat treat machined to remove any distortion that has occurred during the heat treat process. We first grind the outside rails that are in contact with the upper after heat treat. Next, we machine the inside bore where the bolt is doing the work. This ensures the gas rings are not damaged and that the weapon cycles and charges smoothly. These standards are not just met, but we exceed them on every operation during the machining processes and this effort gives our carriers a superior finish with no machining lines.
Toolcraft machines each carrier to last for thousands of rounds and that is why we can offer with confidence a Lifetime Warranty on our products. These standards have given each consumer the confidence that when they use a Toolcraft bolt carrier group in their weapon, it will do what it was created to do, round after round for years to come.
Below: Toolcraft Nickel Boron (NiB BCG) installed in a partially completed pink themed AR15. The unique Nickel finish is well suited to spiffing up a build.
Below: Cat Approved! Expect great things when you combine the best Nickel Boron BCG (Toolcraft) on the market with the best upper and lower receivers (Aero Precision) on the market.
Below: Complete Nickel Boron bolt carrier group as they come from Toolcraft, fully assembled and ready to drop in.
Below: Disassembled bolt carrier group showing all parts including firing pin, assembled bolt, firing pin retaining pin, cam pin and carrier with gas key.
Below: Detailed shot of Toolcraft gas key screw staking.
Below: This NiB bolt carrier group will be paired with a Ballistic Advantage 16" Fluted Stainless 223 Wylde barrel for the ultimate in reliability, accuracy and good looks.
Below: Suitable for use with 300 Blackout as well as 223/556, a Toolcraft Nickel Boron BCG is used on this pistol build.
Below: Nickel BCG installed in this AR15 upper receiver shows silvery contrast against the dark black finish.
Common Questions About Toolcraft BCGs
Who does Toolcraft make BCGs for?
Toolcraft does not disclose which manufacturers are using their BCGs. It is a closely held secret. The best way to be sure your BCG is made by Toolcraft is to buy it from an authorized Toolcraft dealer.
What markings will my Toolcraft BCG have?
Generally speaking, the carrier will not have markings or a logo of any kind.
Toolcraft manufacturers carriers and sources bolts from U.S. suppliers. For this reason, the markings on the bolts vary from batch to batch. Sometimes they are marked MP or MPI but often they are not marked in any way. Sometimes the Carpenter 158 bolts are marked C158 but more often they are not marked in any way. All Toolcraft bolts are individually MPI tested whether they are marked or not.
Is the staking on my Toolcraft gas key screws heavy enough?
Toolcraft installs carrier keys using mil-spec procedures. This means proper surface prep, sealant and gas key screws torqued to the proper value (both over and under torqued screws can fail). Toolcraft then stakes each gas key screw to the mil-spec. There are a lot of overly staked carriers on the market and this is seen by some as a sign of quality. It is not. Over staking of gas key screws runs the risk of cracking the key in a way that can’t be seen with the naked eye.
Proper gas key installation is a process that involves several steps each done correctly. Toolcraft does it right and confidently offers a Lifetime Warranty on all their products.
What is the difference between Carpenter 158 and 9310 steel?
Carpenter 158 is the military specification (mil-spec) for bolts. 9310 is a more modern steel which can be up to 8% stronger than Carpenter 158. They are both premium steels with a long and successful history of use in AR15 bolts. Either will serve you well!
Can I get a left-handed BCG for a left-handed AR15 build I am working on?
Toolcraft makes left-handed BCGs and we try to keep some in stock in Black Nitride. Please see our Toolcraft Left-Handed Black Nitride BCG page for availability.
What finishes do they come in?
Finishes include Black Nitride, Nickel Boron, Chrome & Manganese Phosphate, Ionbond Diamond Like Coating (DLC), and Titanium Nitride.
What is the best finish for me to get?
This is a very subjective question and the simplest answer is that you can’t make a bad choice! Our biggest seller is the Black Nitride, and it is generally the least expensive. If you are looking to spend more, the Nickel Boron, DLC and Titanium Nitride all offer a very slick feel and easy clean up. The chrome & phosphate finish is perfect for traditionalists. For a more in-depth look at BCG finishes, see our blog post on AR15 BCG Finishes.
Do the Toolcraft Bolt Carrier Groups come assembled?
Do Toolcraft BCGs come with firing pins?
Yes, they do. They come ready to drop in to your AR15.
Do Toolcraft BCGs come with charging handles?
They do not, but charging handles can be added to your order.