6 ARC - Anyone Regret It? Also considering 22 ARC

[LRRPF52]

Factory 22 ARC ammo in 88gr is being reported at 2850 by consumers. Is 6 ARC 90gr ammo shown to be faster by consumers?

6mm ARC has less case capacity than 224 AR/22 ARC, which could even them out. You can amend my statement based on that for the 6mm and 22 variants since I’m used to 6mm AR data going back over the last decade+.

As a general rule though, as the bore diameter/volume decreases, the velocity for the same projectile weights decreases due to overbore choking the amount of pressure that can safely be relieved.

For example, factory 90gr TNT from Federal does 2900fps from my 17.6” Grendel, and 2700fps from the 12”. BC sucks compared to 90gr in 6mm and .224, but it sure loves to be punted out. If you made a streamlined 90gr 6.5mm with a secant ogive and long boat tail, it would be competitive with the others without needing to chase pressure.

 

[JR1200W3]

6mm ARC has less case capacity than 224 AR/22 ARC, which could even them out. You can amend my statement based on that for the 6mm and 22 variants since I’m used to 6mm AR data going back over the last decade+.

As a general rule though, as the bore diameter/volume decreases, the velocity for the same projectile weights decreases due to overbore choking the amount of pressure that can safely be relieved.

For example, factory 90gr TNT from Federal does 2900fps from my 17.6” Grendel, and 2700fps from the 12”. BC sucks compared to 90gr in 6mm and .224, but it sure loves to be punted out. If you made a streamlined 90gr 6.5mm with a secant ogive and long boat tail, it would be competitive with the others without needing to chase pressure.

75gr out of 22 Grendel is around 3100 pending barrel characteristics. I'm betting an 80gr ELDM is easily 2950-3000K without having to push past 60K psi

 

[maxsterling]

To me 22 arc is kinda a little overbore (of course 22 creed is even more), and 22 arc vs 6 arc is somewhat like 6 creed vs 6.5 creed. For decent barrel life and ballistic energy, 6 arc won't fade away (actually it will thrive) just like 6.5 creed that is still the mainstream and even military/police adopted it. 22 arc would definitely be a perfect varmint cartridge though, but beside that I doubt it has any further applications. 6 arc/6.5 creed/300 prc adopted by the government agencies is not for no reason. So I'm happy to keep my howa oryx 6 arc mini action (avg .6 moa) and ba 22" AR (avg 1.0 moa), and in the future when 22 arc factory ammo/rifle is sufficient in the market I would probably consider one for coyote hunting.

 

[YotaEer]

To me 22 arc is kinda a little overbore (of course 22 creed is even more), and 22 arc vs 6 arc is somewhat like 6 creed vs 6.5 creed. For decent barrel life and ballistic energy, 6 arc won't fade away (actually it will thrive) just like 6.5 creed that is still the mainstream and even military/police adopted it. 22 arc would definitely be a perfect varmint cartridge though, but beside that I doubt it has any further applications. 6 arc/6.5 creed/300 prc adopted by the government agencies is not for no reason. So I'm happy to keep my howa oryx 6 arc mini action (avg .6 moa) and ba 22" AR (avg 1.0 moa), and in the future when 22 arc factory ammo/rifle is sufficient in the market I would probably consider one for coyote hunting.

Agree completely. I have an 18” proof 6 arc gas gun that I shoot steel and varmints with frequently. Just got some property to build on and will likely get a cheap 6 arc bolt gun together as a “ranch rifle” of sorts. Will likely load lighter bullets in that and though about going 22 ARC for it, but I want the ability to put 100+ grain bullets in it for deer too when my daughters and nephews are old enough.

I have another 18” 6 arc gas gun in the safe waiting for a thermal. Had to sell that off to fund house stuff. Once I get all caught up I will probably make that 22 arc as it will be a dedicated night gun and flat is best there I found.

 

[MasonSims]

Hey all, I’m new to 6arc and looking to put a 18in barrel in a 556 upper I have on hand. My question is, what barrel is the best shooter? And what gas block/hand guard are you guys running? I’ve read that people have had accuracy issues out of BA 6arc barrels, but is that true? I’m looking to make this a quality small frame DMR topped with a Leupold Mark 5, and an atlas bipod. It’ll fill multiple roles from hunting coyotes and deer, to long range steel plinking. It’ll take me a few months to build, because currently I’m strapped for cash.

Any help is appreciated!

 

[JR1200W3]

Hey all, I’m new to 6arc and looking to put a 18in barrel in a 556 upper I have on hand. My question is, what barrel is the best shooter? And what gas block/hand guard are you guys running? I’ve read that people have had accuracy issues out of BA 6arc barrels, but is that true? I’m looking to make this a quality small frame DMR topped with a Leupold Mark 5, and an atlas bipod. It’ll fill multiple roles from hunting coyotes and deer, to long range steel plinking. It’ll take me a few months to build, because currently I’m strapped for cash.

Any help is appreciated!

Check out the Craddock RTR barrels. I think that's going to be pretty hard to beat for value and price

 

[45-90]

My 6 ARC BA barrel, in a factory Areo upper, was a poor performer with 2" to 2.5" for 5 shots at 100 yds.
I assembled an upper with Proof barrel and a few accuracy techniques and came away with a .5" 5 shot group shooter, at 100yds.
Scrapped the BA barrel and bought another Proof barrel, it too is a .5" shooter too....and sometimes much less.
I've had great success with Proof barrels.

 

[MasonSims]

Check out the Craddock RTR barrels. I think that's going to be pretty hard to beat for value and price

How have the groups been? It’s tough for me to find video reviews on them.

 

[MasonSims]

My 6 ARC BA barrel, in a factory Areo upper, was a poor performer with 2" to 2.5" for 5 shots at 100 yds.
I assembled an upper with Proof barrel and a few accuracy techniques and came away with a .5" 5 shot group shooter, at 100yds.
Scrapped the BA barrel and bought another Proof barrel, it too is a .5" shooter too....and sometimes much less.
I've had great success with Proof barrels.

Yeah I’m probably going to wind up going with proof. It’s just tough paying that much for a barrel. If these Craddock barrels work out though I’ll probably do that.

 

[JR1200W3]

How have the groups been? It’s tough for me to find video reviews on them.

I have his 22 arc barrel. It's pretty good. Much better than the Baldwin gun works 22 Grendel barrel it replaced. Regularly sub MOA. Was Berger 85.5's and Ramshot TAC it is .5moa. I wasn't sure about it at first cuz I was dicking around with Hornady 75 grain eldms which just continued to be inconsistent in every barrel. I've shot them in.

 

[tangolima]

Not regretting anymore. My budget upper build turns out to be the most successful part of my AR experiment. Consistently slightly below 1moa at 150yd with handload with the cheapest bullet I could find ($0.14 a round). I wouldn't mind trying the new .22 ARC next.

-TL

 

[YotaEer]

18” Proof barrel abruptly sped up at 250 rounds. Same load - 29 gr of lever, CCI 450 primers, Hornady brass, 108 eldm 50 thou off lands.

85 degree day so that helps some with the lever powered being temp sensitive, but not complaining one bit.

Bet you could get serious speed out of a 20”+ proof bolt gun…

 

[rlsmith1]

Well, I’m trying to decide if I should spend on a 11.5” or not… after running some numbers, the 80 ELD VT from an 11.5” is in line with or even a little better than a 14.5” 556 slinging 77 SMKs

 

[MasonSims]

Hey all, I’ve been digging a bit more and found a company called Rosco who makes 6 arc barrels and have heard good things about them. Has anyone had any experience with them?

 

[TonyTheTiger]

Hey all, I’ve been digging a bit more and found a company called Rosco who makes 6 arc barrels and have heard good things about them. Has anyone had any experience with them?

I've got a Rosco 5.56 barrel and it's super annoying.
Probably the cheapest barrel I have and it's a dang laser beam.

 

[MasonSims]

I've got a Rosco 5.56 barrel and it's super annoying.
Probably the cheapest barrel I have and it's a dang laser beam.

Do you know of anyone running the new 6arc barrel from them?

 

[TonyTheTiger]

Do you know of anyone running the new 6arc barrel from them?

Can't say that I do.