Brownells’ New Barrels, Uppers, Bolts for the New 6mm ARC Round

1. Look, its another oddball, non-NATO caliber that I’m going to completely ignore.

   • What a coincidence! Me TOO!

2. I’m all for innovation and always welcome new products into the marketplace. But to be honest, there are now so many cartridges available, from 5.56, to .458 SOCOM, to Grendel, to Bushmaster, to .350 Legend, to 6.5 CM, to 6.8 SPC, to .50 Beowulf, to .300 BLK, to this new 6mm ARC, I think the spectrum of caliber needs is covered.

   I think I’m just going to stick with 5.56 and .300 BLK, and let everyone else play with the exotics.

   • Yep….as much as I like reloading and playing around with various rounds, I don’t have any interest in yet another AR platform round. If I want a fast sub-6.5 round, there are plenty of choices and I will shoot them out of a more accurate platform.

     • I just checked Ammoland’s site, and the top three current articles are all about 6mm ARC. No thanks.

3. Already did the 6.5 Grendel. Which has turned out to be a waste of time.

   • Care to elaborate?

4. Where is the advantage over 6.5 Grendel? You can buy a complete upper with bolt for less and ammo is easily available, if not so much as 5.56 or 300 Blk.

   • Wolf steel case 100gr FMJ (non-magnetic bullet) shoots an honest to god .75-1.0MOA out of my 16″ Wilson Combat barrel with a velocity standard deviation acceptable for shooting well past 500yds.

     Costs (even during the current panic) less than even the cheapest brass case 556 FMJ.

     Hornady 123gr SST puts an absolute HURT on whitetails as far as I’ve dared to shoot them with it (~150yds) and is no more expensive than premium hunting/match ammo in 556, 6.8, or any of the other AR15 rounds

     My only frustration with Hornady going all in on the 6 ARC is it means more companies will probably drop any Grendel specific development in favor of this newer round. Would have liked to see an updated Precision Hunter offering for the 6.5 Grendel with a specially designed ELD-X similar to the 123gr SST for the lower operating velocities of the Grendel.

     • Yep, I am not gonna abandon my Grendel…plenty of ammo choices and cheap enough to run without having to reload (I will just save my brass cases for later with how cheap the Wolf is). I suspect this one is going to fall flat with so much competition.

   • People have been doing 6mm PPC and 6mm Grendel wildcats for years; IIRC you can get slightly higher BC in the same cartridge OAL, but the actual bullet weight & muzzle velocity aren’t going to be far enough off to differentiate it in performance from Grendel much. Basically a slightly more target-shooting-optimized Grendel. Sort of like how 6.8SPC is the same ‘thing’ but optimized for shorter barrels & machine guns.

     My concern after seeing the cartridges side by side, is whether 6.5G will fit in barrels chambered for this new round. Of course, they’re so similar –only about a half-millimeter apart– that firing the oversized 6.5mm bullet may not even be dangerous in practice (though I still wouldn’t recommend it, of course), as opposed to 5.56 & 300 blackout.

     Marketing wise…I find it hard to believe anyone excited about this round doesn’t already own a 6.5G or a 6.8SPC or a 277Wolverine or other similar intermediate-power ~6mm cartridge from the myriad available. This market segment has been popular for some time, already –and long enough to show that no one has the ‘magic bullet’ best solution. So that makes it even harder for this new round; the only hope it has at success lies in the accessory market that Brownells appears to be cultivating; if they can provide a complete ‘ecosystem’ for the round (ammo, components, bolts, barrels, reamers, gages, dies) at a reasonable price and sponsor some cool applications like uppers or bolt actions, it stands to reason the round will acquire a following. So far, i don’t think a single company has been able to successfully pull that off with a new cartridge, but Brownells has been on a roll, lately.

     Until & unless steel-case FMJ starts coming out, it isn’t gonna unseat Grendel, though. Especially since mag options are still the weak point of both .

     • It works the other way around the 6mm ARC will fit in the 6.5G barrel and cause trouble.
       I have a lot of 6mm and 6.5mm Creedmoor, they are long, heavy, and have same ammo swap risk. If DoD has bought into it, and it appears they have, then it should stabilize a market for it. If you can get a fluted barrel that shoots sub MOA between 500 and 1,000 yards then it will complement your 300 BO AR pistol CCW truck gun, providing backup long range in a portable, lighter weight, and affordable package. So why not, reloading 6mm is a hoot, lots of options and interesting capabilities.

5. I see prairie dog possibilities, low recoil for shot impact viewing, more wind resistant than 223 for those windy South Dakota days. But Im cheap and Im guessing these will be 1.25 per round. Not to mention I havent found an AR yet that can out shoot my $200 Savage 12FV rifles.

6. If I wanted something that is much stronger in stopping power than the 5.56 NATO round, and still reduce operational cost by maintaining the usability of the AR platform’s mags and BCG, I would stick with the tried and true .300 BLK. No need for me to burn unnecessary cash during these times with the latest “hot exotic” rounds.

7. 6mm Creedmore Short?

   • Next we will hear from the Gov. on the blasphemy of 6mm ACR, and what the fires of Hell will be like for anyone that DARES to challenge the Holy writ of the ‘Gospel of 6.5 Creedmoor’…

8. The next big fad will be the SIG .277 Fury when the Army trials are over.

9. “out of a 24-inch barrel.”

   Yet another vunder cartridge.

10. Seems the never ending quest to make the AR-15 something it isn’t continues. Let’s face it, the fact that it was designed around .233 greatly limits what can be done with it. All we get are niche cartridges with very limited range of usefulness. An AR-15 is best left being what it is. If you want something else, get a new rifle platform.

    • Or older rifle platform like AR 10.

    • Could someone explain the advantages over 5.56mm? I like the AR-15, but there are times to change platforms, as suggested, the AR-10.

      I’m not one for small improvements.

      I do not yet own an AR-10, but as the next NATO caliber will work for that platform. I’ll start with 308 as that will be available for 25+ years.

      • higher BC, higher velocity, heavier bullet. The 6mm ARC was also built around the heaver 6mm bullets ie 103 and 108 grain.

        • Try Tubb’s 6mm DTAC 115gr rebated boar tail with closed tip bullet, for best aero performance

11. IMO, current military adoption directly and indirectly contributes to the success of any weapon or caliber… no one’s really buying brand new Beretta 92s and 30.06 rifles anymore. Hornady really did optimize this well and for much better shorter barrel performance than 224 Val. I can see this taking off equally as fast as 6.5 Creed of not faster – the military can simply buy new uppers, swap them and go.

12. What bolt face are we talking about 6.5 Grendel type 1 or 2 (.135 vs .125)? Important to know for those who build their own uppers.

    • Great question, I’ve asked both Brownells and Hornady that question, no response yet.

    • Almost assuredly it is the “type 2” as the “type 1” is and old hack to be able to use 7.62×39 bolts and isn’t even official. According to Bill Alexander, what people are calling “type 2” is the standard bolt face.

      • Thanks, good news, I went all in on this thing today,

      • Ugh. I got that exactly backwards. Type 1 (.136) is the “Grendel” bolt face and type 2 (.125) is the “7.62×39” bolt face. Sorry for the confusion cause by my brain fart.

        • Double Ugh!! (I’m really batting 1000 here). I was right the first time. (Face palm)

          The Grendel bolt face is .136 deep and is referred to unofficially as “type II”. That is the one that almost assuredly be used for 6mm ARC as it is the official (original) standard.

          The 7.62×39 bolt face is .125 deep and is the hack to use 7.62×39 bolts and is referred to unofficially as “type I”. This one is the most uncommon bolt face though you have to watch out when you are buying bargain basement Grendel barrels and bolts.

          Sorry again for the confusion. My brain really farted hard and I jumped in with my follow on (incorrect) comment before I confirmed and reset my brain. That is one of the problems with the unofficial “type I / type II” nomenclature. They are easy to confuse, even for those of use who have been shooting Grendel for a while.

          The good news is that if you buy a Grendel bolt today from any reputable manufacturer it will be the correct (.136 deep) one. Just check to make sure it is the .136 depth.

          • Time out I have a Faxon 6.5 Grendel Type II is this going to work on 6mm ARC or not

13. Anybody have information on the barrels. SAAMI indicates a twist of 7.5 and a head spacing of 1.1901 min 1.201 max but nothing I can see that would tell my which type 6.5 Grendel bolt is appropriate. Brownells list two manufacturers Ballistic Advantage in 1:7 twist and Faxon in either 1:8 or 1:7, their data is inconsistent. Oden Works has long barrels with 1:75 twist and non-standard gas systems. So there is the affordable fluted 3R, 5R, or P5 refiled barrel in proper twist?

    • Also where is the muzzle velocity data for barrel length??

14. Is that a bazooka in brownells gun safe?

15. This article is old. However, I did jumped in and very glad I did. I got their Faxon 20″ ordered in June delivered in late August. Test firing around labor day. getting about 1.25MOA. But the handling difference between my LR308 6mm Creedmoor and this 6mm ARC in an AR-15 frame is a wonderful lighter weight experience. So much so that all my LR308 frames are now relegated to the storage rack.
    I also ordered a CMMG 20″ barrel in late June because they said delivery in 2 to 4 weeks. Received the barrel in October. It shoots .7 to 1 MOA. One of the reasons is the barrel extension. The FAXON is a straight up M4 like extension, the CMMG version has been modified to open up the feed ramp teeth. This helps with concentricity of the loaded round. These long 6mm bullets stick way out and can be leveraged, bend or have tips dented during chambering which opens up accuracy, a classic problem in gas guns.
    Overall, 6mm ARC is a great option for a versatile long range AR. It is a great complement to a 300 Blackout AR pistol truck gun. No need for 7.62×51 much any more. However, ammunition is getting very expensive bought good pile back in August for about 89 cents a round. Now like everything else if you cannot get it they are scalping for $2.50 and up. Since, 6mm bullets are available and if you have a supply of small rifle primers you can reload fairly economically. Lee Precision has all the support stuff you need for this caliber. Enjoy, I am. Remember it is a gas gun and you need BTFMJ class bullets. No SP soft lead tips, it is a gas gun.
    PS Hornady has free full reloading data with barrel length performance adjustment.

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