Microbest Premium Grade M16 Bolt Carrier Group - Nickel BoronThe truth is, not all bolt carrier groups for the AR15/M4/M16 platform are created equal.And, yes, there are only a handful of premium grade BCG manufacturers. Even a BCG from the same manufacturer can be made to varying levels of quality. Why?
Because very few of us, when shooting our rifle, need a BCG of the highest quality that our lives may depend upon it. Most shooters will do well shooting with a BCG that is "good enough."
Well, here is the good news. Charlie's and our sister company, Potomac Armory, went in search of the best premium grade BCG, and worked with Microbest to design the specs to the best that can be. No skimping on steel quality, cheaper hex bolts for the gas key. All the best materials, and the highest grade quality testing: High Pressure Testing and Magnetic Particle Inspection (HP-MPI) on a shot-peened Carpenter 158 bolt, and other upgrades. Many brands that sell rifles to the US military depend upon Microbest, and we believe you can too. We also asked Microbest for the best exterior compounds to resist salt water, corrosion and provide natural lubricating properties, just in case our shooters were not in a position to add special oils to their components. This is what Microbest and Potomac Armory developed.
The Microbest Nickel Boron BCG is not just another component for your AR-15/M16/M4 platform rifles. This is a top-tier product designed for those who demand the best. Whether you're a competitive shooter, a tactical professional, or a firearm enthusiast, this BCG is built to deliver superior performance and reliability.
What sets this BCG apart is its Nickel Boron exterior coating. Nickel Boron is an advanced metal finish that offers high resistance to wear and corrosion, as well as an ultra-low coefficient of friction. This means that the BCG operates smoothly, even under high-stress conditions, and requires less lubrication compared to BCGs with other finishes. This superior lubricity ensures reliable operation, even when the rifle is dirty or under-lubricated.
One of the standout features of this BCG is its Nickel Boron exterior coating. Nickel Boron is an advanced metal finish that offers high resistance to wear and corrosion, as well as an ultra-low coefficient of friction. This means that the BCG operates smoothly, even under high-stress conditions, and requires less lubrication compared to BCGs with other finishes. NiB is 40% more resistent to wear than chrome.
The Nickel Boron BCG is particularly beneficial for those shooting shorter barrels or using suppressors, as these conditions can increase the stress on the bolt. The BCG's superior lubricity ensures reliable operation, even when the rifle is dirty or under-lubricated.
Nickel Boron coating is harder than Tennifer, Melonite, Nickel Teflon and Hard Chrome, with Rockwell Hardness rated at Rc72. What does this mean? It means that the surfaces that this BCG comes in contact with are not as hard as the BCG. This is harder than steel, brass and aluminum. Think of a diamond on glass. NiB has a slippery finsih, with a lubrious ration of CoF .07. It is easier to clean than many finishes: wipes clean in most cases. With NiB, there is less maintenance and longer usage between cleaning cycles and enhanced performance. Unlike some chrome finishes, NiB will not chip, flake or wear.
Imagine a BCG that not only enhances the performance of your rifle but also simplifies maintenance. The Nickel Boron BCG is easier to clean compared to standard BCGs with a phosphate finish. The slick surface of the Nickel Boron finish does not hold dirt and grime as much, making cleaning a quicker and more straightforward process. Plus, its silvery finish adds a touch of style to your firearm, setting it apart from the rest.
Choose the Microbest Premium Grade M16 Bolt Carrier Group - Nickel Boron for your rifle. Experience the difference that a high-quality, reliable, and durable component can make in your shooting performance. Whether for competitive shooting, tactical applications, or just for the sheer enjoyment of shooting, this BCG is an excellent choice that delivers on all fronts.
Microbest is an OEM manufacturer for some of the best military grade bolts and carriers and full bolt carrier groups. Those names and others. Maybe some of the others do not demand High Pressure Testing or shot penning, or the most premium of bolts and steel allows. Some of those names, like Colt and BCM sell for premium prices to have a letter stamped on the side, or a logo engraved, and the reviews for these brands always top the charts of the best available BCGs on the market. That is not by chance. Some of the best names in BCGs depend upon Microbest to make their bolt carrier groups.
Charlie's brings you the best of the best, and a price that is much lower that it should be. Why? Because you are not spending money on fancy packaging or brand marketing, or legacy names that command a premium. And, because Charlie's and Potomac Armory has purchased in volume to bring a great savings to our customers.
The Microbest M16 Full Auto capable bolt carrier group ships full assembled, for your AR15, M16, or M4 with a Nickel Boron finish throughout the carrier, bolt and gas key. Chrome-lined BCGs are great, but you only get the chrome-lining where the bolt moves in the carrier, not where the carrier moves inside the upper receiver. Nickel Boron gives you NiB everywhere, including the corridor for the firing pin. This BCG is machined to meet and exceed USGI specifications. This M16/M4 carrier includes the proper Mil-Spec gas key. Gas key is secured to carrier via USGI domestic manufactured upgraded Grade 8 fasteners and properly staked per Mil-Specs. These properly hardened parts ensure a strong staking and proper gas system functioning.
This Potomac Armory selected Microbest BCG comes with a number of upgrades to the typical commercially mass produced BCG, like shot peening to help improve strength and even features small improvements like a precision ground gas key interface on the carrier to help secure the gas key in place. Even the cam pin has subtle improvements, like a solid film lubricant that helps reduce wear when the bolt is unlocking. The firing pin is hard chrome plated to prevent breakage. This BCG assembly will ensure that your AR-15 will run reliably for many years to come. All this, and now add the NiB coating everywhere in the assembly, and you have a very refined piece of machinery for your weapon.
Any reputable manufacturer, Microbest included, will state their testing protocol for their bolt carrier groups. The tests determine whether the BCG can hold up under stress and pressure. Your BCG is the “heart” of your rifle – it needs to hold up. Generally, two tests are performed. Magnetic Particle Inspection (MPI) and High Pressure Testing (HPT). A quality BCG will be proof-marked with “MPI" or "HPT” or something similar if it’s been through the process. Microbest bolts are labeled MPI and individually tested for high pressure, and labeled for C-158 steel, which is one of the best steel alloys for bolts.
Magnetic Particle Inspection, or MPI, is where the bolt carrier group is magnetized and then temporarily coated with magnetic iron particles, usually themselves coated with a dye that reacts to ultraviolet light. The particles will group themselves in defects and cracks (if any) and glow intensely under the UV light. The Microbest bolts selected by Potomac Armory are MPI inspected and so labeled.
High Pressure Testing, or HPT, subjects the BCG to pressures generally in excess of the usual pressure of the firing sequence. This overpressure tests to see if the BCG can hold up to sustained live firing. Many brands will specify a sample to be high pressure tested. Potomac Armory has specified that Microbest individually test every BCG, as if your life depended upon the bolt not breaking.
In so many ways, a proper M4 or AR15 bolt carrier group is the heart of a truly robust and reliable fighting rifle. Microbest provides OEM services to manufacturers which fulfill requirements for our armed forces. With Microbest components all meeting and exceeding military specifications, you can be assured that this bolt carrier group, selected by Potomac, will be the reliable core component of your AR-15 or M4 rifle.
Comment from sfptac.com: "The Microbest BCG is a top-tier product. It's reliable, durable, and performs exceptionally well. The Nickel Boron finish is a nice touch, adding to its overall quality." (Date not specified)
Comment from snipershide.com: "Microbest BCGs are well-regarded in the shooting community. They are known for their high-quality manufacturing and excellent performance." (Date not specified)
Aero Precision PRO BCG
Bravo Company Bolt Carrier Group
Sons Of Liberty Gunworks BCG
Sionics NP3 BCG
BRT Chrome BCG
Microbest
Microbest
Geissele