Where is 6arc going?

padfoot 37

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Aug 23, 2021
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Wanting to build a 6arc, looking at bartlin or krieger barrels from a couple makers but im hesitant since they are expensive for how new the cartridge is. Wouldnt mind if there was a couple more major ammo companies like federal winchester or remington and a major mag like a pmag or lancer for the 6 arc/6.5grendal before i spend that kind of money on a barrel. Anyone know anything about if its growing in popularity or if its dying? Really like the concept and want to handload for it but dont want to be stuck handloading only in 5 years. Thanks. Also, whats you favorite barrel length for the 6arc?
 
I have a proof steel 18" in 6mm ARC... it's a hammer with factory ELDX ammo.
I'm using "E-Lander" aluminum mags from Brownells... at the time they were the highest rated... I have had zero issues so far.

Right now is going to be a tough time for any new cartridge, with all the supply chain issues and with the wars going on sucking up materials... but I'm optimistic that 6mmARC is going to be successful.
 
I have a proof steel 18" in 6mm ARC... it's a hammer with factory ELDX ammo.
I'm using "E-Lander" aluminum mags from Brownells... at the time they were the highest rated... I have had zero issues so far.

Right now is going to be a tough time for any new cartridge, with all the supply chain issues and with the wars going on sucking up materials... but I'm optimistic that 6mmARC is going to be successful.
Im looking at the numbers and stuff and for targets at longer ranges it has alot more to be excited about for me then 6.5gren or 224val. Id really want another ammo option and a more common mag before i buy to help longterm staying power but maybe i will just buy a barrel anyway.
 
I'm half way to my 6 ARC build. I just need charging handle, Proof 20" carbon barrel and gas block.

-Sharps Livewire lower
-Magpul PRS lite stock
-Triggertech Diamond 2 stage
-Magpul K2+ grip
-Seekins Safety
-Aero enhanced buffer tube
-JP Silent Captured buffer
-JP enhanced upper
-Sgt of Arms 17.5 ARCA handguard

but after seeing actual velocity #'s out of a 18" Criterion (2410 fps) with factory 108 ELDM's and how dirty it is after 100rds it's scaring me. The owner wipes down his BCG after the 5th stage to prevent issues.
 
My 20" Proof with factory 108 ELDM is doing 2640-2660. No excessive fouling that I have noticed. It seems to be about the same or slightly less than my other 556 AR's as far as carbon. Barrel cleans easily and the JP carrier just wipes clean. It's an AR, they can run dirty with lots of rounds through them without cleaning contrary to what the internets says.
 
I'm half way to my 6 ARC build. I just need charging handle, Proof 20" carbon barrel and gas block.

-Sharps Livewire lower
-Magpul PRS lite stock
-Triggertech Diamond 2 stage
-Magpul K2+ grip
-Seekins Safety
-Aero enhanced buffer tube
-JP Silent Captured buffer
-JP enhanced upper
-Sgt of Arms 17.5 ARCA handguard

but after seeing actual velocity #'s out of a 18" Criterion (2410 fps) with factory 108 ELDM's and how dirty it is after 100rds it's scaring me. The owner wipes down his BCG after the 5th

My 20" Proof with factory 108 ELDM is doing 2640-2660. No excessive fouling that I have noticed. It seems to be about the same or slightly less than my other 556 AR's as far as carbon. Barrel cleans easily and the JP carrier just wipes clean. It's an AR, they can run dirty with lots of rounds through them without cleaning contrary to what the internets says.
Ive heard a couple who said it ran dirty, thats often been out of shorter barrels. Is that a gas length thing or a barrel length thing or just coincidence?
 
Ive heard a couple who said it ran dirty, thats often been out of shorter barrels. Is that a gas length thing or a barrel length thing or just coincidence?
I run all of my AR's (except my 3 gun AR) suppressed and it naturally dirty but for some unknown reason my buddy's 6 ARC ar is STUPID dirty. I don't know if it's the powder used in factory 108 eldm ammo or a larger case volume. He will stop using factory ammo once he accumulates 500 pieces of Hornady brass. Once that happens he'll be using LeveRevolution or CFE 223 which we'll keep an eye out for how dirty it is.
 
I run all of my AR's (except my 3 gun AR) suppressed and it naturally dirty but for some unknown reason my buddy's 6 ARC ar is STUPID dirty. I don't know if it's the powder used in factory 108 eldm ammo or a larger case volume. He will stop using factory ammo once he accumulates 500 pieces of Hornady brass. Once that happens he'll be using LeveRevolution or CFE 223 which we'll keep an eye out for how dirty it is.
Ive had 556 guns that were way dirtier than others for no apparent reason... idk if its similar or not.
 
This was my buddy's 6 ARC's bolt after 130 rds. He says "It runs extremely dirty. Like. Horribly dirty. Even unsupressed." I compared his bolt to my .223/556 bolt (uncleaned after 200rds) and his is significantly dirtier than mine.
 

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Wanting to build a 6arc, looking at bartlin or krieger barrels from a couple makers but im hesitant since they are expensive for how new the cartridge is. Wouldnt mind if there was a couple more major ammo companies like federal winchester or remington and a major mag like a pmag or lancer for the 6 arc/6.5grendal before i spend that kind of money on a barrel. Anyone know anything about if its growing in popularity or if its dying? Really like the concept and want to handload for it but dont want to be stuck handloading only in 5 years. Thanks. Also, whats you favorite barrel length for the 6arc?
The problem with the 6 ARC was the timing of it's release.

That said people rightfully so have the right [and reason] to be skeptical of new cartridges. There has been more than one where people got deep into them only to discover half baked engineering or poor execution or a bit of both.

The 6 ARC though is here to stay in my opinion. It's really nothing new in a sense. Hornady didn't try to invent a proprietary magic bullet design for it nor any other weak points. There are hundreds of options (if not more than that) of 6mm bullets. The bolt has been tested and tried in the real world with the Grendel for how long? It's been tried in public for ages and had the kinks worked out for the most part. About the ONLY thing that is 'new' are the specific case dimensions of 6 ARC brass. Everything else has had decades of field testing behind it.

Based on that alone there is zero reason to think the 6 ARC will 'fail'. It really just boils down to how bad you want one and if that desire translates to 'right now' or not.
 
This was my buddy's 6 ARC's bolt after 130 rds. He says "It runs extremely dirty. Like. Horribly dirty. Even unsupressed." I compared his bolt to my .223/556 bolt (uncleaned after 200rds) and his is significantly dirtier than mine.

What length gas system is he running in that 18" barrel?

My 21" runs ~2,680fps with factory 108gr ELD and ~2,705 with factory 105gr bthp. If your buddy is getting nearly 300 fps less than that in an 18" and it's freakishly dirty, it sounds like something is wrong, causing really low pressure for some reason.
 
What length gas system is he running in that 18" barrel?

My 21" runs ~2,680fps with factory 108gr ELD and ~2,705 with factory 105gr bthp. If your buddy is getting nearly 300 fps less than that in an 18" and it's freakishly dirty, it sounds like something is wrong, causing really low pressure for some reason.
his reply "fixed gas block. Standard rifle gas tube. And an A5H0 buffer and spring. " He says it shoots awesome with low SD's.

I will be using a Lantac Enhanced carrier with JP Grendel bolt, JP silent buffer and JP adj gas block with a 20" Proof carbon.
 
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What length gas system is he running in that 18" barrel?

My 21" runs ~2,680fps with factory 108gr ELD and ~2,705 with factory 105gr bthp. If your buddy is getting nearly 300 fps less than that in an 18" and it's freakishly dirty, it sounds like something is wrong, causing really low pressure for some reason.
It kinda sounds like low pressure but not experienced enough to say for sure.
 
his reply "fixed gas block. Standard rifle gas tube. And an A5H0 buffer and spring. " He says it shoots awesome with low SD's.

I will be using a Lantac Enhanced carrier with JP Grendel bolt, JP silent buffer and JP adj gas block with a 20" Proof carbon.

The ARC isn’t new, it was a very popular Grendel wildcat for a long time. I think it’s here to stay, a fantastic little cartridge. It kind of got released at the worst possible time as it relates to supply chain. I think had this come out in 2016 we’d have seen Starline jump in with brass etc. Currently they can’t keep up with std offerings. I’m hopeful that we may see some new brass & powder options for these if/when things settle down.

Cartridges like the ARC & Valk require slower burning powders vs .223/.308/300BO/6.8. Nothing is free so increased fowling Is a penalty.

It can be minimized if you pay close attention to maximizing gas system efficiency. Tight bolt tail - bore clearance, best 3 pc rings, & tight smooth finished ring run bore. Rifle + 1 on 18-20” or + 2” on 21”+ make sense for these. I’ve got a RL +2” on a 22” ARC with light wt carrier & std JP silent capture. Still runs dirtier than a well built AR on a diet of fast powder, but not terrible. I have heard of gas tubes clogging with lever so I’ll keep an eye on that. I can go 100+ round match or whatever without issue.

Do yourself a favor. Replace the 1 pc JP gas ring for a 3 pc ring set. 1 pc rings are DAF. That alone will lower gas requirements and the better seal will reduce fowling.

Lever is the dirtiest powder I’ve ever used. It also gives the best speed with heavy pills in ARC & Valk. You can also turn the gas down some with Lever.
 
Wanting to build a 6arc, looking at bartlin or krieger barrels from a couple makers but im hesitant since they are expensive for how new the cartridge is. Wouldnt mind if there was a couple more major ammo companies like federal winchester or remington and a major mag like a pmag or lancer for the 6 arc/6.5grendal before i spend that kind of money on a barrel. Anyone know anything about if its growing in popularity or if its dying? Really like the concept and want to handload for it but dont want to be stuck handloading only in 5 years. Thanks. Also, whats you favorite barrel length for the 6arc?
Its a been around for 20ish years (Robert Whitley and the 6mm AR). The ARC is just a stadardized version w/ incremental changes. Its not going anywhere.
 
This was my buddy's 6 ARC's bolt after 130 rds. He says "It runs extremely dirty. Like. Horribly dirty. Even unsupressed." I compared his bolt to my .223/556 bolt (uncleaned after 200rds) and his is significantly dirtier than mine.
Also my experience.

Pictured is fired factory brass loud/ suppressed.
 

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Also my experience.

Pictured is fired factory brass loud/ suppressed.
Looks about par for the course for my LVR loads suppressed with both my ARC and Grendel. My suppressed .223 loads are probably a little cleaner, but not a ton, with much lower amounts of 8208.
 
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Also, if you guys were to build a upper with a highend barrel like a krieger or bartline, what exactly would you do? Length twist rate gas length profile maker? Thanks.
 
I think 6ARC is the best all around cartridge for the AR-15. I think it's here to stay. 224 valkyrie should have been a 6mm. 6mm will have higher BC bullets and more energy than anything 224. High BC 264 bullets are too heavy for cartridges designed to work within the mag well dimensions of the AR-15. Sounds like magazines still need a little bit of work, but it's the one to beat right now.
 
Also, if you guys were to build a upper with a highend barrel like a krieger or bartline, what exactly would you do? Length twist rate gas length profile maker? Thanks.

Totally depends on what you want to do with it. For PRS or anything past 700yd routinely, I'd go 24-26" and heavy.

Utilitarian, 16 or 18" medium profile, or maybe a Proof Carbon barrel.
 
Also, what is the weight of your gun if you dont mind me asking?

It shoots fricking amazing across the board..just a note I did opt for the matched bolt. Some groups at 100, no bs, this tube shoots.


Weight comes in just a smidge under 15lbs.

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I got a Shaw 22" barrel for $220 and it's been excellent. I typically see ~.7 to 1.2 MOA out of factory ammo and in the .4 to .6 MOA range out of handloads. Mine likes 109 grain Bergers and 110 A-Tips with LVR or CFE-223. I mostly want to use it as a range toy and extend the distance as far as possible. I'll work up a load for a high BC hunting projectile this summer. It likes to be kept reasonably clean, so maybe every 200 rounds I give it a clean & lube job.

Down the road I want to build a lighter / more maneuverable 6 ARC with a CF barrel and lighter parts.

I've been using Hornady brass and Lapua 6.5 Grendel brass. I've got 500 Lapua, so I'm set for the short/mid term. Planning to pick up some more soon.
 
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I got a Shaw 22" barrel for $220 and it's been excellent. I typically see ~.7 to 1.2 MOA out of factory ammo and in the .4 to .6 MOA range out of handloads. Mine likes 109 grain Bergers and 110 A-Tips with LVR or CFE-223. I mostly want to use it as a range toy and extend the distance as far as possible. I'll work up a load for a high BC hunting projectile this summer. It likes to be kept reasonably clean, so maybe every 200 rounds I give it a clean & lube job.

Down the road I want to build a lighter / more maneuverable 6 ARC with a CF barrel and lighter parts.

I've been using Hornady brass and Lapua 6.5 Grendel brass. I've got 500 Lapua, so I'm set for the short/mid term. Planning to pick up some more soon.
What is your rifle weight of you dont mind me asking? Not opposed to a bit heavier gun since ill do alot of range stuff with it off a bipod but dont want to get too heavy i hate taking it hiking.
 
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My 18" Proof CFW barrel likes the Hornady 108 ELD-X. Correction: ELD-M.

It was interesting to watch the velocity pick up (20 fps) and the SD drop as the barrel got the first 200 rounds through it. I think it is the best shooting precision small block AR' I've ever owned.

I always shoot suppressed. I've tried the following suppressors on it:

Thunder Beast Dominus CB
Thermal Defense Solutions Nocturnal
OSS HX-QD 7.62 TI
CGS Helios QD TI

It's sub-MOA with all four. More dirty with some than others.

Velocities out of shorter barrels with this same lot of ammo:

14.5" Proof CFW 2502 fps
12.5" Bartlein by Craddock Precision 2392 fps
 
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What is your rifle weight of you dont mind me asking? Not opposed to a bit heavier gun since ill do alot of range stuff with it off a bipod but dont want to get too heavy i hate taking it hiking.

It's kind of like it's owner - a bit on the flabby side - 11.9 pounds. But remember, this is a range toy to shoot out to the shorter side of ELR. It has an Atlas bipod, a 22" barrel and a 5-25 PST Gen 2, so I wasn't even slightly worried about the weight. And that's why I want to build a recon / hunting rifle with a 16" or 18" CF barrel and lighter weight parts. I won't go overboard on the ultra-light side because I want it to be durable.

6 ARC sz.jpg
 
It's kind of like it's owner - a bit on the flabby side - 11.9 pounds. But remember, this is a range toy to shoot out to the shorter side of ELR. It has an Atlas bipod, a 22" barrel and a 5-25 PST Gen 2, so I wasn't even slightly worried about the weight. And that's why I want to build a recon / hunting rifle with a 16" or 18" CF barrel and lighter weight parts. I won't go overboard on the ultra-light side because I want it to be durable.

View attachment 7866584
Sweet rifle dude! Thinking i might do a 20in varmint bartline barrel. Try to straddle the fence for weight and capability.
 
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My 18" Proof CFW barrel likes the Hornady 108 ELD-X.

It was interesting to watch the velocity pick up (20 fps) and the SD drop as the barrel got the first 200 rounds through it. I think it is the best shooting precision small block AR' I've ever owned.

I always shoot suppressed. I've tried the following suppressors on it:

Thunder Beast Dominus CB
Thermal Defense Solutions Nocturnal
OSS HX-QD 7.62 TI
CGS Helios QD TI

It's sub-MOA with all four. More dirty with some than others.

Velocities out of shorter barrels with this same lot of ammo:

14.5" Proof CFW 2502 fps
12.5" Bartlein by Craddock Precision 2392 fps
Suppress is a thing id like to get to someday...
 
View attachment 7866578View attachment 7866579
My 18" Proof CFW barrel likes the Hornady 108 ELD-X.

It was interesting to watch the velocity pick up (20 fps) and the SD drop as the barrel got the first 200 rounds through it. I think it is the best shooting precision small block AR' I've ever owned.

I always shoot suppressed. I've tried the following suppressors on it:

Thunder Beast Dominus CB
Thermal Defense Solutions Nocturnal
OSS HX-QD 7.62 TI
CGS Helios QD TI

It's sub-MOA with all four. More dirty with some than others.

Velocities out of shorter barrels with this same lot of ammo:

14.5" Proof CFW 2502 fps
12.5" Bartlein by Craddock Precision 2392 fps
108 ELD-M or 103 ELD-X for clarification. Also, have you tried the 106 TAP?
 
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I wouldn't hold your breath for magpul or Lancer mags. Magpul claims to have tried and was unable to get the polymer to do everything they wanted. Metal mags are deffinately better and there's high quality ones available.

Amend 2 made a poly mag and they are shit.
 
I have a CLE/ Douglas. I have only fired 12 rounds so far of the factory 103's. I have not got a velocity of the rounds yet, but it has shot 5/8 with only 12 rounds fired. It is a 20" rifle gas. Looking forward to some Leverevolution and 90gr Sierra Gamechangers. Big hopes for that set up. I will be expecting 2800+ from it.
 
This is why all of a sudden you have a hard time getting 6.5g brass.

The 6arc guys are snatching it all.

So if you shoot 6.5g don't post where or when brass becomes available thinking you're helping a guy with a grendel out.

The mfg's have not kept up at all with the arc
 
108 ELD-M. My bad.

I didn't know there was a 106 grain loading.
The 106 is the LE TAP load. Accuracy (sorry, precision!) seems to have been secondary to terminal performance. That’s a nice way to say that, compared to the ELDM, ELDX and Black, it sucks, er, I mean, has lots of room for improvement.

If you get a chance to try the ELD-X, let us know. I have gotten groups from it right there with the ELD-M and Black.
 
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I wouldn't hold your breath for magpul or Lancer mags. Magpul claims to have tried and was unable to get the polymer to do everything they wanted. Metal mags are deffinately better and there's high quality ones available.

Amend 2 made a poly mag and they are shit.
Yeah, got a reply from magpul on them making a 6.5gren/6arc mag

Good morning, I hope all is well with you. We appreciate you taking the time to reach out to express the desire for a 6mm ARC mag. I'll be sure to pass your word onto our team, however I'm not sure of any current plans to come out with that mag. New products are generally announced at the beginning of each year with SHOT Show, so be sure to keep an eye out around then each year. You may also sign up for the newsletter on our website for new product updates looking forward!

Have a great week,


So thats that i guess.
 
I believe the future of the 6mm ARC would really take off if and when the U.S. military would ever adopt it across all branches of our armed forces and just not special op units. From CQB SBR's to 1,000+ yds along range rifles, the 6mm ARC checks a lot of boxes, in an AR15 sized and weight rifle along with okay barrel life.

www.gunsandammo.com › editorial › hornady-6mm-arcU.S. Military Adopts Hornady's New Cartridge: 6mm ARC
I agree, imho it makes more sense to me than the 277 fury ar10 but im no expert on what the military needs or wants.
 
When Hornady first posted the specs for the 'new' 6mm ARC bullet they used a 24" barrel on a bench bolt action rifle. Then Barrett announced that they were using the round to give to spec ops people in an 18" CF barrel. Can't quite compare the 2 (bolt vs AR) numbers wise. It will shoot a very long ways and still have the ability to thump a BG. If you are going to bench/prone shoot this get the longer barrel.

I had a seldom used Barrett 300BO that I took and converted to 6 ARC. Having an unused AR keeps the cost down tho. All I needed was a new barrel (Proof 18" CF), a correct bolt, and magazines. While I waited for the barrel, every time I went into a gun shop (way too often) I bought 2-4 boxes of 6ARC 108 ammo. When everything else was getting expensive these didn't have the popularity yet so was buying them for $12.50-18/box. Its hard to find them now but they are out there. I could sell a lot of my rifles but this will be a keeper.
 
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When Hornady first posted the specs for the 'new' 6mm ARC bullet they used a 24" barrel on a bench bolt action rifle. Then Barrett announced that they were using the round to give to spec ops people in an 18" CF barrel. Can't quite compare the 2 (bot vs AR) numbers wise. It will shoot a very long ways and still have the ability to thump a BG. If you are going to bench/prone shoot this get the longer barrel.

I had a seldom used Barrett 300BO that I took and converted to 6 ARC. Having an unused AR keeps the cost down tho. All I needed was a new barrel (Proof 18" CF), a correct bolt, and magazines. While I waited for the barrel, every time I went into a gun shop (way too often) I bought 2-4 boxes of 6ARC 108 ammo. When everything else was getting expensive these didn't have the popularity yet so was buying them for $12.50-18/box. Its hard to find them now but they are out there. I could sell a lot of my rifles but this will be a keeper.
Im really hoping that it will be that for me as well