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12 Best AR-15 Bolt Carrier Groups (BCG) [Hands-On]

A sports car needs a great engine.  An awesome AR-15 needs a great bolt carrier group (BCG).

But there’s A LOT of choices.

Best AR-15 BCGs
Best AR-15 BCGs

From full-auto to lightweight, different coatings, MPI inspections, and more.  It can make you go nuts (the above is probably half of my BCGs).

But don’t worry, we’ve got our list of our go-to BCGs.

BCG Aliens meme

We’ll cover some of the choices and then our favorites for different purposes (and budgets)…from mil-spec to competition and even some builds just for looks.

Table of Contents


Full Auto vs Semi-Auto Bolt Carrier Groups

First off, “full-auto” BCGs are legal and don’t magically make your AR-15 automatic firing.

The slightly longer and heavier bolt carrier group has an additional lug at the rear of the bolt carrier group.

BCG Shroud, AR15
BCG Shroud,

On a full-auto AR-15 or M16, this rear lug pushes the sear release downwards which allows full auto (or burst) fire.  In a semi-automatic rifle, this has zero effect on how the gun functions.

Semi-auto carriers are now the ugly step-child of the BCG world and don’t have much purpose…like commercial buffer tubes and stocks.

Semi Auto (top) Vs Full Auto (bottom)

The semi-auto ones have an extra cut that takes out some mass.  Mass that should help with reliability.

Semi-auto versions used to be significantly cheaper than FA versions, but now the difference isn’t as drastic.

Main lesson…get a full-auto weighted BCG if reliability is a concern.

Mil-Spec Bolt Carrier Groups

Mil-Spec is a bit of a buzzword in the AR community.  Mil-Spec generally means the rifle is built to pass military specifications.

simple buzz lightyear meme
If only everything were this easy.

Mil-spec doesn’t mean greatest ever, or worst, it’s just in spec to a military contract.  Here’s some of the important bits:

  • High Pressure Tested (HPT)
  • Magnetic Particle Inspected (MPI)
  • Heat treated and shot peened
  • Bolt carrier machined 8620 steel
  • Carpenter 158 steel bolt
  • Chrome lined interior bolt carrier key and bolt carrier
  • Torqued and staked gas key screws
  • Coated with a matte black mil-spec finish

HPT and MPI Tested

See that “high pressure tested” and “magnetic particle inspected” above?  That means each bolt is individually tested at a proof load.

mpi testing bolt
Here’s a shot of magnetic particle inspection applied to a slightly different type of bolt.

Usually it’s printed onto the bolt (either as MP or MPI).  But not all the time.

Aero Precision BCG
Aero Precision BCG with MP tested bolt

If it doesn’t say in the description…it probably is only batch tested.  And you never know if a batch is 10 or 1000 BCGs.

Again, if it’s a duty or self-defense gun…I’d opt for something MPI and HPT tested.

Different BCG Coatings

Mil-spec means phosphate coated and is matte and a little bumpy.  Which does its job but does requires more cleaning than newer coatings.

PSA Phosphate & Nitride BCGs
PSA Nitride BCG (Top) and Phosphate BCGs (Middle and Bottom)

New coatings come and go…and they all say they are the latest and greatest.  Here’s my opinion…

  • Nitride is black and shiny.  And is easier to clean.
  • While Nickel Boron (NiB) is silver and shiny.  And easier to clean.
  • And more exotic stuff like Titanium Nitride (TiN) is gold and pretty.  And easier to clean.

Now let’s get on with our actual picks!

12 Best AR-15 Bolt Carrier Groups (BCG)

1. Bravo Company Manufacturing (BCM) M16 BCG

Let’s just start with our editor’s pick for a branded mil-spec BCG.

If you ask most people online what’s their go-to BCG…the vast majority is going to be BCM’s M16 BCG.


Nothing much to say except it’s mil-spec everything and has a great reputation.

Gold Standard Mil-Spec BCG
at Brownells

Prices accurate at time of writing

Prices accurate at time of writing

What’s your take on the BCM?

Readers' Ratings

4.94/5 (720)

Your Rating?

2. Brownells Nitride M16 BCG

Looking for something a little more budget?

Brownells Nitride M16 BCG gives you the added benefit of the Nitride finish which makes it slicker and easier to clean.

Brownells Nitride BCG
Brownells Nitride BCG

It’s MPI tested and otherwise mil-spec…except that the bolt is made of 9310 steel instead of Carpenter 158.

The chances of that mattering for an average shooter that puts even a few thousand rounds downrange a year is super slim.

In the back of your mind you’ll know it’s not mil-spec…but it’s about half the price of the BCM.

at Brownells

Prices accurate at time of writing

Prices accurate at time of writing

3. Rainier Arms Match Grade Nitride BCG

Want something in the middle…that’s mil-spec AND Nitride coated?

Check out Rainier Arms’ Nitride BCG which meets or exceeds mil-spec.

Rainier Arms Nitride BCG
Rainier Arms Nitride BCG

Plus has a different/more aggressive cut on the carrier around it’s logo…if that matters to you.

And priced at a nice price point between the BCM and Brownells.

at Rainier Arms

Prices accurate at time of writing

Prices accurate at time of writing

4. WMD Guns Nickel Boron BCG

Nickel Boron (NiB) used to go for a lot more in price but now they’ve stabilized at around the BCM pricepoint.


I do like them in terms of increased lubricity and ease of cleanup.  Plus it the silver color pops out in your upper receiver.

My WMD NiB BCG been chugging along in my AR pistol for a few thousand rounds…and I’ve only needed to wipe it down with some cleaner and microfiber cloth.

My pick if you want to go with the best-known name in the NiB BCG game.

Best Nickel Boron
at Brownells

Prices accurate at time of writing

Prices accurate at time of writing

5. Aero Precision BCG

One of my favorite uppers and full rifle manufacturers is Aero Precision (review of their M4E1 5.56 upper).

Aero Precision M4E1 Upper with ATLAS Handguard
Aero Precision M4E1 Upper with ATLAS Handguard

And the BCG that comes with their upper has always gone bang through many thousands of rounds.  Full mil-spec everything.

Aero Precision BCG
Aero Precision BCG

Great combo with their builds if you’re buying stuff from them anyways unless you want a different coating.

at Aero Precision

Prices accurate at time of writing

Prices accurate at time of writing

6. Palmetto State Armory (PSA) BCG

This is where you can go stupid cheap on builds…that still work reliably (PSA 3 AR-15s Review).

PSA 5.56 & .223 Wylde
PSA 5.56 & .223 Wylde

Their mil-spec phosphate BCGs are a little bumpy but they work.

PSA BCGs Disassembled
PSA BCGs Disassembled

And they are actually the cheapest in the whole article.

at PSA

Prices accurate at time of writing

Prices accurate at time of writing

Looking for something a little lighter?

Best Low-Mass or Lightweight Bolt Carrier Groups

Low-mass or lightweight bolt carrier groups are relatively new on the market.  We also have a whole guide just for choosing a lightweight bolt carrier groupso be sure to check that out if you want to know more.

Lightweight and Regular BCG's
Lightweight and Regular BCG’s

A low-mass BCG serves two purposes.  

If you are following the current fad of super lightweight AR-15s you want to trim weight basically everywhere.  You can cut a few ounces off by using a low-mass bolt carrier.

A Mil-Spec BCG is about 11.6 ounces, but you can much lighter now…especially with cuts and exotic materials like titanium.  The primary advantage of this is to reduce recoil.

gun recoiling into shooters face
Too much recoil can impede accuracy.

Since the bolt carrier group is shot backward towards the shooter the weight of it affects recoil.

The more mass you have coming rearward the more recoil you’ll feel. 

Any reduction in recoil and firearm movement, in general, helps you stay on or get back on target as you fire.  A low mass BCG moves faster which could increase your rate of fire, but skill makes a bigger difference in cyclic rate than bolt weight in a semi-auto gun.

Brownells TiN Lightweight BCG, Rear
Brownells TiN Lightweight BCG, Rear

Why do regular bolt carrier groups still exist?

A lightweight BCG is designed for a tuned rifle and a builder who’s willing to toss an adjustable gas block on and really tune the gun system.  The heavier standard BCGs are better suited to running any kind of ammo through any kind of gas system.  

So, if you’re building a SHTF, zombie-apocalypse-proof, rifle…go with a regular BCG.  

Building a performance-tuned competition rifle with an adjustable gas block?  Go with a light-weight BCG.

Here’s some of our favorites…

7. Faxon Lightweight BCG

Want to go lightweight for competitive shooting?

Before you had to go with different materials for the carrier like aluminum…which turned out to not be a great idea.  Aluminum carrier rubbing an aluminum receiver led to the carriers being used up in a few thousand rounds.

But now you have aggressive weight reducing cuts like with the Faxon Lightweight BCG.

Faxon Lightweight BCG
Faxon Lightweight BCG

It comes in at a much lighter 8.5 oz (compared to a full auto 11.6 oz).

Faxon Lightweight BCG, Rear
Faxon Lightweight BCG, Rear

And has worked out great in my Faxon builds (Faxon Barrel Review).

Faxon Upper Receiver and BCG
Faxon Upper Receiver and BCG

Lose the weight but keep the steel.

Most Affordable Light BCG
at Faxon Firearms

Prices accurate at time of writing

Prices accurate at time of writing

8. Brownells Lightweight BCG

Brownells has thrown a contender into the ring with their lightweight BCGs.  And now with different coatings.

I of course went with their Titanium Nitride (TiN).

Brownells TiN Lightweight BCG
Brownells TiN Lightweight BCG

Their bolt uses 9310 steel but again…it is likely never going to matter.

It weighs in a little lighter than the Faxon at 8.2 oz probably due to the one additional cut.

Brownells TiN Lightweight BCG, Rear
Brownells TiN Lightweight BCG, Rear

Save a little with their Nitride…but might as well go big or go home.

at Brownells

Prices accurate at time of writing

Prices accurate at time of writing

9. Rubber City Armory (RCA) Titanium BCG

My current go-to for competition shooting is the RCA BCG but costs a pretty penny since the carrier is Titanium.

RCA Titanium BCG
RCA Titanium BCG

I’ve shot many thousands of rounds through it and it still looks new…not even that many wear marks on the touch points.

RCA Titanium BCG, Front
RCA Titanium BCG, Front

Total weight is 7.87 oz which isn’t that much less than the other steel cut lightweights…but I like having the complete full-auto form factor.  9310 bolt but that is the standard for lightweight builds.

Best Light BCG
at Brownells

Prices accurate at time of writing

Prices accurate at time of writing

10. Brownells Titanium BCG

And of course…Brownells has entered the game with their version of the Titanium BCG.

Brownells Titanium BCG
Brownells Titanium BCG

It comes in at 7.9 oz and is indistinguishable from their regular Nitride version except when you pick it up.  Again…9310 bolt.

I’m still testing this one out but it might be a good substitute for the RCA one at some decent savings.

at Brownells

Prices accurate at time of writing

Prices accurate at time of writing

11. Walker Defense Titanium BCG

Another recent addition from the makers of the most hi-tech AR-15 muzzle brake…one that’s 3D printed from Inconel (think rocket ship engines).

Nero Muzzle Brake
Nero Muzzle Brake

You can check that review out in Best AR-15 Muzzle Brakes.

But you’re here for BCGs…

Walker Defense Titanium BCG
Walker Defense Titanium BCG

And there’s their Titanium BCG for 5.56/.300 BLK.

If you look closely you’ll see that the Titanium carrier is black (DLC: diamond like coating) while the bolt is silver (nickel boron).

The DLC was chosen for high wear resistance and a low coefficient of friction.  While the Nickel Boron on the 9310 steel bolt was chosen for being easy to clean, having a low coefficient of friction, AND with the benefit of heat dissipation.

Something something about the bolt having similarities to a heat sink and making contact with fresh/cooler air.

Main thing is that it looks great and is performing great so far too.  With that comes a Gucci price though…

But…the makers have hooked you up with coupon code “PewPew” for 10% off.  The link here and below will auto-add it.

at Walker Defense Research

Prices accurate at time of writing

Prices accurate at time of writing

12. Bootleg Adjustable Carrier

My newest BCG and one that has a trick up its sleeve…

Normally if you want to control the gas going back into your AR-15 you’ll need to pick up and install an adjustable gas block.

Bootleg Upper and Adjustable BCG
Bootleg Upper and Adjustable BCG

Bootleg’s adjustable carrier gives you this capability in the BCG itself with a couple clicks on the side.

So far I can definitely feel the recoil difference between the different settings.  And although there’s only 4 settings so you won’t get down to the perfect setting for your rifle and loads…it’s a great system if you don’t want the hassle of swapping out a gas block.

at Optics Planet

Prices accurate at time of writing

Prices accurate at time of writing


That does it for BCGs…there’s lots to choose from…

Our Favorite BCGs
Our Favorite BCGs

But if mil-spec is the name of the game…get the BCM.

Gold Standard Mil-Spec BCG
at Brownells

Prices accurate at time of writing

Prices accurate at time of writing

If you’re looking for something mil-spec and a little upgraded with a Nitride coating…get the Rainier.

at Rainier Arms

Prices accurate at time of writing

Prices accurate at time of writing

To enter the lightweight BCG game…start with the Brownells Steel Lightweight.  But be sure to get the most out of it with an Adjustable Gas Block.

at Brownells

Prices accurate at time of writing

Prices accurate at time of writing

What kind of BCG do you run?  There’s so many BCGs out there so let us know what we missed.  And check out the rest of our Best AR-15 Upgrades.

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81 Leave a Reply

  • Bull o' the Woods

    All this NiB and no mention of the Young Manufacturing chromed M16 BCG and bolt?

    July 23, 2021 12:13 pm
  • Last laugh

    You could have just said Toolcraft, the company that actually manufactures 3/4 of the items you listed.

    June 5, 2021 8:12 pm
  • Chris

    Shout out to Voodoo Innovations. Awesome BCG at a reasonable price.

    May 27, 2021 7:09 pm
  • Don Robbins

    What about AR-15’s by Geissele?
    They are a top manufacturer of complete rifles, carbines and pistols in their newer Super Duty line. And for parts they make the best trigger assemblies in the business. Love my AR-15 10.5” pistol!

    May 1, 2021 7:08 am
  • Mark

    Anyone have any experience with Sharps Rifle Co. BCGs?

    February 16, 2021 5:37 am
    • David, PPT Editor

      We haven't used one yet but there has been very negative feedback we've heard.

      February 16, 2021 6:38 am
      • Blacjac

        Your feedbackers are lying to you , one of the best 556 BCG on the market! The bolt and carrier made of G7 steel an M-16 BCG

        March 24, 2021 6:57 pm
  • Guy named mike

    I’m building an ‘AR ‘ 10 , it’s the first real build that I’ve committed to . I’ve helped others and watch a lot of gun Jesus for entertainment mostly but my experience with metal fabrication really grew when I tried to ‘ make’ a machine gun in my garage in my spare time. The reason I decided to post here has to do with tolerances of different aspects and of degrees of temper and the utility of intentional variable of the former or later. So to say that it’s all mil spec is a kind of buzafication of information . In fact so to cut corners in the learning curb for would be buyers? Of a given product or application of a feature.
    Is any of this sounding like a worthwhile version of the truth?

    November 27, 2020 3:13 am
  • Daniel Kukoly

    what is the major difference between a 8620 BCG and a 9310 BCG? I am trying to do some research between the two and can't really come up with a PROs and CONs. Can you provide some input? Is a 9310 steel BCG better steel than a 8620 steel BCG?

    November 23, 2020 7:06 pm
  • Guy Doing Stuff

    Your Magnetic Particle Inspection image of a bolt is actually a Liquid Penetrant Inspection image.

    November 11, 2020 11:06 pm
  • Jim

    Can anyone recommend a BCG compatible with an LMT .308? I'm sure they have some advances with their $500 BCG but mine won't be in for months. LMT says their MARS-H platform is SR-25 and the only BCG that will work in their own BCG.

    September 15, 2020 12:31 pm
    • David, PPT Editor

      Since LMT says the only BCG that works is theirs, I would go with what they say. They have made a lot of changes to BCGs as a whole and really know their stuff.

      September 15, 2020 3:33 pm
  • Razor_Regiment


    September 2, 2020 12:41 am
  • GoodGuy

    If you haven’t tried the Black Rain BCG, you are missing out on the smoothest running BCG on the market today. Runs better than BCM (which I love), at al slightly lower price point.

    August 22, 2020 12:48 pm
    • gerald Torres

      which style should i get black nitride or nickel boron?

      September 25, 2020 11:30 am
  • John Morris

    Well wondered how you left out Lantac ?

    August 9, 2020 11:58 pm
    • Jimney Cricket

      ^^ same

      June 19, 2021 8:10 pm
  • john newsome

    Not so sure the absorption of the recoil energy, which is a fixed value of the design of the gas system, would equal less felt recoil just by changing to a lighter mass of the BCG without addressing all the other components, gas block, recoil spring tension, and buffer mass. Change one and you have to adjust the rest.

    July 28, 2020 7:59 pm
  • Johnson McDagger

    Man it sucks to see how much the prices have gone up since this article was posted just a few months ago. Everything is $20+ more than it was

    June 26, 2020 9:16 am
    • Hastings

      No joke , it’s crazy right now , hard enough to even find anything in stock at that.

      July 17, 2020 4:25 pm
  • Paul Coon

    Ok guys I love guns and building them and customizing them but I dont know everything about everything by far and now I'm on researching BCG's. But my question is how is a Titanium one not the best choice easily? And I say this because it's alot stronger of a steel and lighter, so ad a DLC coating and I don't understand how it doesn't automatically win? Once again I'd love some feedback and comments as I'm researching! Thanks guys!

    June 5, 2020 10:44 pm
    • David, PPT Editor

      Titanium doesn't offer as much over steel in this case as one might think. The carrier itself is a very low wear part, the only part that really takes any wear is the cam path itself and that isn't enough to become a problem very often. The weight saving is great if you're trying to tune the rifle, but it does require tuning. Combine this with the fact that a titanium BCG is very expensive and it's hard to call it the "best". It's a good option, for some people, but it's not a great option for a lot of people.

      June 5, 2020 11:59 pm
  • Steve J.

    Hmmm...seems you left out an industry leader who actually makes BCGs and not rebrand someone else's. You may want to look into Barnes Precision Machine next time.

    May 10, 2020 9:56 am
  • Scott S

    On the topic of recoil, I get the idea of 'less mass moving might = less felt recoil', but what about less mass in the BCG to absorb the recoil? Heavier revolvers (e.g, stainless vs. titanium) have less felt recoil, heavier semi-auto pistols (stainless slide vs. aluminum etc.) are known for less felt recoil, so why would that not translate to the AR platform when talking about the BCG mass? Seems the lighter BCG would at least make the recoil "snapier" than with a heavier BCG?

    March 30, 2020 3:47 pm
    • David, PPT Editor

      Normally a low mass BCG is combined with an adjustable gas block, less mass means less force is needed to move it. An adjustable gas block lets you tune the gas so that less force is put into the BCG, stacked on top of less mass coming back at you and you have a reduced recoil impulse that is also not snappy!

      March 30, 2020 4:18 pm
  • Jon Wright

    Great info. Many thanks

    January 16, 2020 5:11 pm
  • Paul

    Kind of seems like a commercial for Brownell‘s, Hard to trust a list without fail zero on it.

    November 20, 2019 6:52 pm
  • tangofoxtrot

    Odin works have been perfect in one of my grendels.

    October 22, 2019 3:00 am
  • Bull o' the Woods

    I have an old Colt AR15 semi-auto BCG. The bolt itself is standard Colt milspec. I have several spare bolts and don't need an extra. I'd like to purchase a quality bolt carrier without a bolt. I have yet to find a source except for some sketchy surplus sellers. Every quality source I have seen sells only complete BCGs. Any suggestions? Or am I stuck with replacing the entire BCG to get an M16 bolt carrier?

    October 18, 2019 1:01 pm
    • tangofoxtrot

      Check JP Enterprise but I'm thinking colt bcg have a proprietary cut to them??

      October 22, 2019 2:57 am
    • Gary

      Try contacting E2 Armory - ask for Kaylee. She’ll be able to help you out.

      December 3, 2019 6:10 am
  • Jason Lee Elder

    LMT Enhanced Bolt Carrier and Bolt! Trouble is finding one.

    August 31, 2019 3:15 am
    • Beau Rippy

      Exactly. I kept scrolling, looking for the Lewis. Shocked it and a few others didn’t make the list when I saw of the some names that did.

      October 13, 2019 11:40 am
    • Chris

      The LMT BCG is the best on the market. This clown not mentioning it, and then listing 10 absolute pieces of trash is embarrassing for a “tactical” website. should ban this idiot from writing anything and only let professionals with experience and actual knowledge speak.

      August 25, 2020 10:59 pm
  • Gerald

    I have ADM,AAC,PSApremium,and Colt bcgs.I firmly believe that tha Colt bcg is the best of the milspec bcgs.Until I see proof of long term high round count reliability of the boutique bcgs Im sticking with Colt.Bcm and the filthy 14 have shown reliability after many thousands of rounds.

    August 3, 2019 3:56 pm
  • Scott

    I ve had zero issues with my blackened, polished, Nib-x bcg from WMD.... smooth as glass... wipes clean with a rag...

    July 7, 2019 1:53 pm
  • RICH

    This article was a great read if you're a newbie unfortunately this article forgot to actually mention some of the best BCG's on the market. I own a few from cryptic Coatings, Radian, and toolcraft. I can attest to the cryptic coatings as they are by far the best. They may be a little bit pricey but you get what you pay for.

    June 7, 2019 5:41 am
    • Mr. Untactical

      Rich, I'm one of those aforementioned "newbies." The first lesson I've learned is that - apparently - a rifle is never really finished. I've doubled the price of my first AR (Ruger AR556) with optic and other upgrades. Now, I'm thinking new BCG... for no real reason.

      I've been eyeing the Radian Enhanced BCG and might throw in the Raptor charging handle and ambidextrous safety while I'm at it. I've heard lots of good things about Radian and it sounds like you're a fan as well?

      November 18, 2019 10:28 am
  • Jacob

    Young MFG BCGs if you want real precision and aerospace component process technology. Do check them out.

    May 29, 2019 9:54 pm
  • Adrian

    What brand is the full auto in the comparison that you did? Full auto semi auto comparison

    May 3, 2019 5:35 pm
  • Tyler

    I believe 9310 steel is stronger than C158. All the “high pressure” bolts like JP Enterprises are made with 9310 and state it’s stronger than C158, which is just mil-spec (the minimum standard).

    April 26, 2019 9:30 am
  • mike

    There is no best bcg.Buy one with a great reputation,for me thats Colt.I have Lmt,Psa,Lwrc they all work but Colt is inspected,tested and in spec.THE MOST TESTED.

    April 24, 2019 3:33 pm
  • Wild Bill

    Been running LANTAC E-BCG's in all my AR's with no issues. A little expensive but my AR's run so smooth!!

    March 31, 2019 10:51 am
    • Ben M

      Lantac is very high quality, tough as hell, and highly sought after. Surprised it didn't make the list, it is far superior to Bravo.

      June 27, 2020 3:37 pm
  • Danny

    What about Sharps Rifle Company XPB BCG.

    March 11, 2019 12:22 pm
  • Mrfunkmon

    Primary Weapons Systems DI BCG should be #1, followed by POF, BCM #3. IMO

    March 5, 2019 6:12 pm
  • robert a lasley

    A bcg i purchased a while back that have had zero issues with is sharps rifle co with its reliabolt. The lugs on the bolt semi angled cut sloping down toward the muzzle end. The marketing hype said the quit the endurance test at 5000rds with no failures. Either way i got it it's been great and they have been making them for years now

    March 2, 2019 2:27 pm
  • Alex

    I’ve actually had two BCGs gas keys come loose, one being an early Fail Zero NiB BCG. I can’t remember what the other was but it was a plain basic one. I got an LMT BCG in my main AR that hasn’t had an issue yet and I have a lightweight VDI BCG that has their Lifecoat coating and the gas key is actually integrated into the BCG so there are no screws that can loosen or need to be staked. With that VDI BCG, it is one less worry.

    March 1, 2019 5:25 am
  • Farkosh

    I would disagree with the title of the article that these are the 10 best. A few definitely deserve to he there, but not all.

    I would have liked to see mention of enhanced bolt carrier groups like the lantac or radian that have different dimensions and can help improve accuracy. Additionally I would recommend other bolt materials like the sharps that's made out of s7 tool steel, or JP enterprises who makes amazing products like a variable mass carrier, and enhanced bolt that has a different lug cut to ease lock, strengthened cam pin hole, and low friction ring seals to reduce wear. I also agree with a lot of others here that cryptic coatings should be considered, they are the slickest bcgs I've ever used with the lowest friction on the market. Their mystic black has a friction coefficient of 0.01... for comparison NiB is 0.5-0.8, DLC is new and its 0.02-0.15(something else to consider when looking at coatings), TiN I believe is 0.45.

    I'm not affiliated with any of these brands, just things I've learned while building. Otherwise I really enjoy your articles, thanks.

    February 28, 2019 7:12 pm
    • Eric Hung

      Thanks Farkosh, lots for me to add in the future update. Definitely Cryptic since I've seen several people mention that already.

      March 1, 2019 12:06 pm
    • Ruffone

      Farkosh, I am with you on this. The title should read, “These are the 10 best that I use since most of them are affordable.” I use and have used a lot of the different BCGs out there, both cheap ones and high priced ones. I make it a habit of trying everyone I can get my hands on personally. Currently I’m using BCM, F-1 Firearms, Cryptic Coatings, Lantac, JP Rifles and a few others. I find the Cryptic Coating BCG to be slickest and easiest to clean of them all. Each one of them have their place whether it be light weight for competition ARs or ones that work better for silencer use. I had to go through several different BCGs along with several different manufacturers to find one that cycled correctly in my 45 Raptor. And the one thing that was not mentioned that has a big impact on what BCG works best in what AR is whether or not you like keeping your ARs dripping in oil or dryer than most. So once again we get a list of someone’s opinion on what they think are the best BCG, ask 1000 different people and they’ll probably give you a 1000 different lists.

      February 14, 2021 5:00 pm
  • Brian

    I used Toolcraft nitride bcg’s for my last 2 builds and have been more than happy with them. Easy to clean and a great price point.

    February 28, 2019 6:20 pm
    • Notalima

      ^That. Right there.

      February 28, 2019 7:20 pm
    • Ed

      Not sure how he failed to include Toolcraft. Aren't they the OEM for some of these Mfgrs? Also DLC coating is becoming popular and more common.

      May 21, 2019 1:25 pm
      • Stephen

        My understanding is they are OEM for BCM BCGs.

        April 21, 2020 1:53 pm
    • Friend of the Pod

      As someone who's tactically thrifty, I've only used Toolcraft BCGs in my builds(*), and have never had a problem. I was surprised they weren't included too.

      * One is actually a BA BCG, but it's really a re-branded Aero BCG, which in this particular case is really a Toolcraft BCG.

      October 9, 2020 10:21 pm
  • Mike M

    The fact that no Cryptic Coatings BCGs are here means the whole article is useless

    February 28, 2019 5:38 pm
    • PSJ

      ^^Nuff said^^

      March 1, 2019 1:15 am
  • Yugbe

    There will only be one bolt that I will use for the future, and it comes from Sharps. The BCG's above are all great options, but the bolt itself is a different story. :)

    December 10, 2018 7:04 am
  • Roquer

    I am reading thru this article on bolt carrier groups. I am interested in a full auto BCG. I was wondering if I need to purchase a specialized upper to fit a full auto BCG since the back of it is longer and a smidgen heavier than standard ones?

    November 30, 2018 12:36 pm
    • David, PPT Editor

      Nope, SA and FA BCGs have the same dimensions and will fit in any standard AR-15 upper!

      November 30, 2018 12:37 pm
  • Connor H

    I LOL’d at the Magnetic Particle tested “bolt” picture. That was absolutely hilarious. Well done sirs. Also, to everyone, be careful with NiB bolts, and be sure to check headspace on every build. I’ve read numerous stories of stacking tolerances from some manufacturers, due to the thickness of the coating. Please check the headspace on every build. Go/No-go gauges are too cheap to make excuses about safety concerns.

    PewPew, it’d be great if you could do an article about headspace, its importance, and how to check it. I’ve run into more semi-experienced shooters than I can count who had no idea, or only a vague idea, what headspace is, and had never checked it on any of their bolts/barrels/rifles. I cringe every time, then pull out my handy dandy gauges and prepare to give a lecture.

    July 5, 2018 7:25 pm
    • James

      Yes what he said. NiB coatings do add thickness and most bolt makers pay attention to the bolt face but for get about the lugs, where a small buildup of carbon will lock your bolt up. Also NiB has less friction does not mean it does not need lube. The AR15 use the lube not only as lubricant but also captures particles. Its great NiB will run fine with a small amount of lube I recommend using normal amount of lube.

      August 14, 2018 12:21 pm
  • michael

    what makes the BCM bcg better than the bcg it copies COLT

    June 25, 2018 7:15 pm
    • Memorial Rifle Range

      All Colt makes these days are the extractors, The pony is a mere shadow of once greatness..

      February 28, 2019 5:14 pm
  • Evan

    Are the Phosphate bolts stronger than both NiB & TiN? I really like the idea of easier cleaning, but if the hardness isn't as great, then since I have to clean anyway... I've found NiB & TiN BCGs for $100 & $120, respectively.

    June 16, 2018 3:37 pm
  • Patriot

    Nothing beats POF milspac + BCG...

    May 20, 2018 5:42 pm
  • Rob

    What about lwrci's keyless BCG

    May 12, 2018 1:50 pm
  • Dennis Bixler

    So maybe a dumb question, but a new BCG makes it easier to clean and maybe less recoil, right?
    So if you don't mind cleaning your current and the recoil isn't a big deal, what other reason is there to change?
    Just asking since I'm enjoying learning about all of the fun you can have with the adult lego set!

    April 7, 2018 1:56 pm
    • David

      If it does what you want it to do, there isn't a need to change. A better one might last longer or be a bit more reliable in bad conditions, but that depends on what you currently have Vs. what you might upgrade to.

      April 7, 2018 2:24 pm
  • A & P Armory

    Full auto bolt carriers are essential if you run a fostech echo trigger.

    March 25, 2018 7:50 pm
  • Mike

    sorry I've owned a lot of BCG's and any discussion of the best BCG that doesn't include Cryptic Coatings at the very top is not worth reading. Easiest to clean, best customer service, and no, I'm in no way affiliated with them. I have put them in all of my AR platforms in the past 2 years.

    January 30, 2018 4:35 pm
    • John

      I agree to that!

      February 5, 2018 7:04 pm
    • Eric Hung

      Thanks Mike, I've actually never heard of them!

      February 13, 2018 9:05 pm
    • Mike B

      Had never heard of them. Thanks for sharing.

      February 20, 2018 1:38 pm
      • Mike B

        and liking what I found on their site.

        February 20, 2018 1:39 pm
    • James Jarmon

      Cryptic is the best Ive ever used as well. 15k rounds and counting on my carbine. Been throw 4 barrels, but the BCG looks near new.

      June 13, 2018 9:53 pm
      • Tom Smith

        4 barrels in 15K rounds?? wow!! Please tell us which barrels so we can avoid!

        June 22, 2018 6:45 pm
    • iichael

      what makes them better than Colt,Bcm because they might be easier to clean? Let me remind you that a quality Ar will run very dirty as long as it's wet.

      June 25, 2018 7:21 pm
      • Ruffone

        But with one of Cryptic Coating BCGs you don’t have to run them dripping wet which is a definite plus when running suppressed.

        February 14, 2021 5:13 pm
  • G. Brunner

    I just purchased a nitride (sometimes referred to as Melonite) finished BCG. It is a surface treatment that unlike coatings will never chip or flake off. It has the lubricity of the NiB, it is cheaper than NiB and it cleans up every bit as easy.

    June 27, 2017 4:51 pm
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