New 6mm Advanced Rifle Cartridge

[rebby]

I believe you answered my question. But I was referring to a "Hand guard" not the actual barrel nut where the gas tube does run through the nut. The Guntec hand guard has to be "Timed" to the barrel nut. What do you recommend as a good starting point to torque the barrel?? I also have a tool to lap the upper receiver. One last question, how do you keep the clearance between the upper and the barrel extension to a bare minimum?? Do you shim it with something??? I really appreciate all of your input!! Thanks again!!

Starting torque will depend on a number of factors about the barrel and muzzle device. What are the details? I can give a recommendation for a starting point but, it would be just that, a starting point. I did misunderstand, timing w/shims to align the hand guard to the barrel nut shouldn't cause an issue.

As far as barrel extension to upper fit, that depends on just how loose it is. If there is a lot of slop to take up, you can use some shimming material. I try to avoid uppers that fit this loose if at all possible. It's somewhat of a hassle to deal w/the shimming material if you ask me. Over the years we've also built the extension up and then turned it on a lathe until it fit snugly then bedded with some Loctite 620. Truth be told, as long as the upper isn't really loose, bedding w/Loctite 620 has yielded results that are just as good. The trick is to avoid a really loose upper if you can (this may be easier said than done, especially in the current market).

 

[Yondering]

My son in law has a Ballistic Advantage barrel and we had to turn the necks on the Lapua brass. You could fire it but the accuracy sucked!! I figured the problem was problem high pressure for to tight of neck tension. I took a fired case and tried to push a bullet in by hand and it would NOT go in. In reality it was only like a .001 thicker than the Starline brass. But in a tight throat that is .002 to much neck tension and will not let the case neck expand inside the chamber. With cold weather if has been put on the back burner for now. I hope to be getting my Shaw barrel in the next month. Not sure how that will shoot. I have read mixed reviews about them, just hoping for the best......

Weird. I wonder if that barrel was cut to one of the 6mm PPC tighter neck dimensions? It used to be (maybe still is) really common to spec a tighter neck in 6 PPC so that your turned necks could fit the chamber with the perfect amount of clearance you wanted. Purely speculation about the BA barrel of course, the only one I have is in 5.56 and it's a good one.

 

[raptor99]

Starting torque will depend on a number of factors about the barrel and muzzle device. What are the details? I can give a recommendation for a starting point but, it would be just that, a starting point. I did misunderstand, timing w/shims to align the hand guard to the barrel nut shouldn't cause an issue.

As far as barrel extension to upper fit, that depends on just how loose it is. If there is a lot of slop to take up, you can use some shimming material. I try to avoid uppers that fit this loose if at all possible. It's somewhat of a hassle to deal w/the shimming material if you ask me. Over the years we've also built the extension up and then turned it on a lathe until it fit snugly then bedded with some Loctite 620. Truth be told, as long as the upper isn't really loose, bedding w/Loctite 620 has yielded results that are just as good. The trick is to avoid a really loose upper if you can (this may be easier said than done, especially in the current market).

Thank you for your reply again!! I totally agree with everything you have said. We have found some real differences in the uppers too. We have actually run across a couple where the lapping tool would not even fit into the upper!! That is nice but would still like to be able to square the face on the upper!! The one thing I have noticed about an upper that is not "Square" is when you tighten the barrel nut you can "Feel" it getting tighter but when the action is squared you start to tighten the nut and it just "Stops" and it is tight...

 

[skyrep]

My son in law has a Ballistic Advantage barrel and we had to turn the necks on the Lapua brass. You could fire it but the accuracy sucked!! I figured the problem was problem high pressure for to tight of neck tension. I took a fired case and tried to push a bullet in by hand and it would NOT go in. In reality it was only like a .001 thicker than the Starline brass. But in a tight throat that is .002 to much neck tension and will not let the case neck expand inside the chamber. With cold weather if has been put on the back burner for now. I hope to be getting my Shaw barrel in the next month. Not sure how that will shoot. I have read mixed reviews about them, just hoping for the best......

The Shaw barrel you ordered, was it for Gas Gun or Bolt Action. I finally got my Shaw barrel for bolt action (Savage). It only has 40 rounds thru it (breaking it in). Was disappointed with the velocities out of a 24" barrel. Hoping it will increase with additional shooting. Time will tell.

 

[rebby]

Thank you for your reply again!! I totally agree with everything you have said. We have found some real differences in the uppers too. We have actually run across a couple where the lapping tool would not even fit into the upper!! That is nice but would still like to be able to square the face on the upper!! The one thing I have noticed about an upper that is not "Square" is when you tighten the barrel nut you can "Feel" it getting tighter but when the action is squared you start to tighten the nut and it just "Stops" and it is tight...

If they're loose and not square, sometimes you can even see the barrel "tilting" as it tightens down. Obviously NOT a good situation to be in for any build!

 

[Yondering]

If they're loose and not square, sometimes you can even see the barrel "tilting" as it tightens down. Obviously NOT a good situation to be in for any build!

Yes for sure. The worst part about that IMO is the uneven bolt lug contact that results from a tilted barrel. I suspect that is one of the biggest causes of broken bolts.

 

[brazz04]

Hornady 6mm ARC Ammunition H81608 108 Grain ELD Ballistic Tip 20 Rounds

Hornady 6mm ARC Ammunition H81608 108 Grain ELD Ballistic Tip 20 Rounds

www.outdoorlimited.com

141 in stock right now

 

[Fret]

CLE is pretty fast. The website said the wait for a barrel is 12-14 weeks. I just went to the range this AM to zero the scope on the BA 6 ARC barreled upper and when I got back there was a CLE email with tracking numbers. It took exactly only four weeks.

 

[raptor99]

The Shaw barrel you ordered, was it for Gas Gun or Bolt Action. I finally got my Shaw barrel for bolt action (Savage). It only has 40 rounds thru it (breaking it in). Was disappointed with the velocities out of a 24" barrel. Hoping it will increase with additional shooting. Time will tell.

It is an 18" for a gas gun. Give your barrel some time. They usually get faster after you have around 150 to 200rds through them. Keep me posted on your accuracy results if you would. Thanks!!!

 

[KnightRaid]

Would anyone happen to know what kind of barrel life can be be expected with the ARC? Mine is a Proof 18” Steel and I was just curious.

 

[TonyTheTiger]

You can take in online and also many website have a affiliate program also.

How much money should we wire to your account?

 

[Bantam1]

Would anyone happen to know what kind of barrel life can be be expected with the ARC? Mine is a Proof 18” Steel and I was just curious.

When I spoke to my contact at Hornady about this last year at SHOT show he said he had over 6000 in his test barrel with no issues. I didn't see the barrel and this was well before the cartridge was announced.

 

[Dino11]

I have been told by those in the know that barrel life should be about the same as .223/5.56 barrels. But their are a lot of variables to put a number of rounds on it.

 

[newageroman]

Got an ATN 4k 5-20 test mounted on top of the 6ARC. The night vision stuff is pretty cool, my first time using it. There is a BC in it I'm wondering how accurate it is. I'm going to use the One Shot Zero and boresighting to zero before I get to the range.

I have some test loads I need to chrono/group before making another batch with what I have left of LeverLoution. That's first because the new Dillon 650 caliber conversion kit for 6.5 Grendel needs to be sorted/tested out.

I'm seeing more ammo show up around here. I was able to snag some 22LR and watch others grumble/complain about factory stuff. This give me a bit of hope but I am betting the primers are going to be used for factory ammo as opposed to sold for reloaders.

 

[Gtscotty]

I'm glad you posted this. I'm shopping for a barrel now. Keep us posted on how they handle it.

My barrel was at Odin Work's shop a few weeks with no word before I got a chance to call. When I did call, the guy who inspected it told me that the crown was indeed messed up and they still aren't sure how exactly that happened.

Not sure why they couldn't just cut and re-crown, but they are sending a replacement. Unfortunately they aren't doing another run of 18" barrels for a while, so my options were either wait for a few months or get a 21" instead. I opted for the 21", but it's really heavier and longer than I wanted, so I'm not sure I'll keep it. I do have all my other upper pieces collected up now, along with 3 boxes of factory 108gr, so maybe I'll just shoot it.

Hodgdon finally updated their load data repository with 6mm ARC data, attached below.

 

[Sutherlandsd]

Welll I am finally almost ready to start shooting this cartridge, I picked up a barrel and stuff off a couple of wonderful hide members to go with my seekins upper and rail thats gathering dust, and amazingly enough traded a bunch of old 45acp .38s and about 1k rounds of bulk .22lr for 14lbs of same lot leverevolution (got 6 lbs of hybrid 100v also lol). I'm hurting for bullets I have almost 500 105 bergers and less than 100 108 eldm's so I'm going to have to do a little work to find some bullets. The range I shoot at opens up their 1000+ range on April 1st and I intend on using this build to introduce friends, family and co workers to long range. I have been using 224valk for this and its done wonderful but there are times that the little valk leaves a barely audible ring on steel at distance and even less movement especially compared to 6,5prc that I'm usually shooting beside them... I'm hoping the arc is a shade better in that respect and I have no intentions of retiring the valk completely. I still need to setup my dillon 550 with a conversion kit so that I am not spending more time reloading than shooting.

 

[jbailey]

I have been using 224valk for this and its done wonderful but there are times that the little valk leaves a barely audible ring on steel at distance and even less movement especially compared to 6,5prc that I'm usually shooting beside them..

6ARC from a semi auto will be nowhere close to a 6.5PRC. You are giving up everything - MV, BC, bullet mass. Maybe 6ARC's precision can hang w/ a 6.5PRC, but that is it beyond the obvious recoil difference (which sounds like why you are thinking about it). It might be a tad better than your 224valk, but don't look for it to be materially better. At 600yds and beyond, it doesn't move steel much nor sound impressive. You can see it, but nothing like a magnum.

Consider following example:
6ARC's 108gr H at 2700fps in sea level air density .... has 540ft-lbs at 800yds
224Valk's 88gr H at 2700fps in sea level air density ... has 440ft-lbs at 800yds

So a 20% increase, but they are both pretty wimpy. Both are huge jumps over the 223Rem however.

 

[Sutherlandsd]

I personally shoot a 6.5PRC but have found that if I am taking new shooters that may or may not like it 28grs of powder vs 55grs of powder and brass that is somewhat available vs prc brass that is basically made of gold...

Muzzle blast of PRC and the slight recoil also make it a little sketchy for new shooters and the biggest reason of all is that PRC is a bartlein barrel thats got a much more limited life than the valk or the arc lol.

But yeah if it will shake the steel a little better or ring it a little louder, buck the wind a little better than the valk and convert a few slightly liberal people to long range shooters then I will be pleased.

 

[Blazin]

Factory ammo in stock, but at $2.50 a round.
https://www.laxammo.com/hornady-6-mm-arc-105-gr-bthp-20-rounds-81604-detail

 

[Dino11]

I was at one of my local gun shops yesterday and purchased six box's of 105 for 24.99 a box. Ammo is out their you just have to look for it. This past week I scored a thousand small rifle and large pistol primers for 99.99 a brick, again you have to look to find them. I am having problems finding powder right now but it will come back in the near future.

 

[raptor99]

Just a quick update. I finally put my 6ARC upper together on Thursday. I bought a Shaw barrel and was told they were not all that great. When I got the barrel on initial insp the barrel appeared to be well done. Nice finish on everything as far as the exterior went. I run a patch through the bore to check it out and it stopped at the gas port hole!! There was a very distinct burr in the barrel where it was drilled. I took a cleaning brush and scrubbed it back and forth and got it broke off. I then cleaned the barrel and took JBs bore cleaner and scrubbed it with that then cleaned it again. It felt and appeared nice and smooth. Since I was going to shoot it with a can I got and adjustable Odin gas block. When I tied to put it on it fell right on the barrel with zero resistance!!!! When I checked it you could actually feel play between the barrel and gas block!! I miked both and the barrel was cut at .747 and the gas block was .753!! So I had .007 clearance!!! This really concerned me. Then when I went to put the barrel in the upper receiver it was also on the lose side. I had lapped and squared the face of the receiver and wanted to use it since they are hard to find now. So I bought some "Green" loctight an used it on both the barrel ext and the gas block. I was really concerned about gas leakage on the gas block so I "Stippled" the barrel on the bottom two thirds of the barrel and was careful with the loctight so I wouldn't plug my gas port hole. I let it set for two days and took it out,with crossed fingers, to try out this morning. My first few rounds for sight in cycled fine and was chucking my brass at about 3:30. I sighted the rifle in with "Factory Black" and then shot a 3 shot group to check my final zero. Three of them went into a .535!! I was shocked and happy with that!! I then started load testing using LVR and CFE with 108,90ELDs most of my 3 shot groups were under and inch with one group of 90ELDs going into a .515 with LVR. Shooting with the can the rifle was getting really dirty and the brass I had sized down must have been just a tad oversized because I started having issues of failure to fire when chambering the first round so I called it a day and came home to clean it. For the first outing I am pleased. No gas leakage around the gas block, it cycles, and it seems to be fairly accurate. The one thing I noticed over my son in laws Ballistic Advantage barrel is that I did NOT get any flyers like he was getting when load testing. We squared the receiver face on his but did not use loctight on the barrel extension. I will keep you posted as load testing progresses I hope to get out to 300yds this week to see how it does........

 

[SBRSarge]

Sounds like a shaky start during assembly, but the end seems to show promise. Hopefully groups stay tight for you, keep us posted.

 

[GONE BAD]

Well I've been working pretty hard rounding up ammo, and loading supplies and just lately I think, its coming together.

Have 8 boxes 108 match ammo, dies, some bullets. The barrel, bolt and magazine should be hear Tuesday.

Hopefully I'll be able to get it together this week and run some rounds through it.
Kinda putting this together without much thought into buffer system and gas block.

Just using what I got laying around
We've all heard the term "crap shoot".

My last attempt at going overboard on a build was an exercise in futility ( BRN from Brownnells).

 

[eddie102870]

first couple of shots out of my 6ARC. when the barrel gets broken in it ought to do a little better

 

[Gtscotty]

Finally caught Leverevolution in stock, one 8lb jug left:

Hodgdon LeveRevolution Smokeless Gun Powder

Hodgdon Leverevolution WARNING: This product can expose you to Lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to – www.P65Warnings.ca.gov.

www.powdervalleyinc.com

 

[eddie102870]

and its gone

 

[scrumpdeleos]

Thinking of going with a proof research 6 ARC barrel in either 18 or 20, what kind of accuracy have people been getting using the factory ELD ammo? I dont have the ability to reload yet due to space confinement and lack of supplies, so for now it will just be the Hornady factory ammo.

Thanks

 

[Fret]

Was able to snag the last 8lb jug of Leverevolution after several tries. Now I can start messing with my 6 ARC project.

 

[eddie102870]

Thinking of going with a proof research 6 ARC barrel in either 18 or 20, what kind of accuracy have people been getting using the factory ELD ammo? I dont have the ability to reload yet due to space confinement and lack of supplies, so for now it will just be the Hornady factory ammo.

Thanks

posted a pic of the first three rounds of my 18 in proof barrel a few post back

 

[scrumpdeleos]

posted a pic of the first three rounds of my 18 in proof barrel a few post back

Is that the 18 or the 20?

 

[eddie102870]

Is that the 18 or the 20?

18

 

[scrumpdeleos]

18

Am I gaining anything significant by going with a 20 or no?

 

[eddie102870]

Am I gaining anything significant by going with a 20 or no?

id think a few more FPS

 

[raptor99]

Load tested at 300yds today with about 7 different groups that shot well at 100yds. I was very pleased again with how well the rifle is shooting. I had one load that had shot a .202" 3 shot group at 100yds with 87VMAXs. I shot two 5 shot groups with this load at 300yds. With one load I had 4 rounds in a .8 and the other I had 4 in a .9!!! The 5th round put one group at 1.9"s and the other at 2.2". I had another group of 87s with CFE that shot a 5 shot group into a 1.6" group. All of my other loads were in the .6 to .9 MOA range at 300yds. This barrel is a shooter and just does NOT foul!! I have yet to see any blue on my patches!!!! I now have a good varmint load and will test some 108s in the next few days and see how they do.......

 

[alamo5000]

I am wondering if anyone can direct me to any short barrel results others may have gotten.

If you have seen any velocity data for lighter to midweight bullets in a 12ish inch barrel I am curious to see it.

Hornady has velocity data for heavy bullets in a 12" barrel but that's all I have ever seen.

 

[Dino11]

Load tested at 300yds today with about 7 different groups that shot well at 100yds. I was very pleased again with how well the rifle is shooting. I had one load that had shot a .202" 3 shot group at 100yds with 87VMAXs. I shot two 5 shot groups with this load at 300yds. With one load I had 4 rounds in a .8 and the other I had 4 in a .9!!! The 5th round put one group at 1.9"s and the other at 2.2". I had another group of 87s with CFE that shot a 5 shot group into a 1.6" group. All of my other loads were in the .6 to .9 MOA range at 300yds. This barrel is a shooter and just does NOT foul!! I have yet to see any blue on my patches!!!! I now have a good varmint load and will test some 108s in the next few days and see how they do.......

I had very similar results as you with one of my 6mm ARC's. It has a match grade Odin works barrel. I have a new rifle delivering this Saturday, it is a Uintah 22" bolt action. This one has a match grade barrel as well. The Odin barrel groups at .5 MOA or better at 100 yards, five shot groups. The new one will hopefully do as well or better.

 

[mrtoyz]

Anyone have good luck with IMR powders??

 

[Alyef]

I am wondering if anyone can direct me to any short barrel results others may have gotten.

If you have seen any velocity data for lighter to midweight bullets in a 12ish inch barrel I am curious to see it.

Hornady has velocity data for heavy bullets in a 12" barrel but that's all I have ever seen.

I am planning on building a 6mm ARC with a 12ish barrel too. Who‘s barrel were you planning on using? The only one i can find online is the Faxon 12.5”

 

[TonyTheTiger]

I am planning on building a 6mm ARC with a 12ish barrel too. Who‘s barrel were you planning on using? The only one i can find online is the Faxon 12.5”

Just have McGowen or X-Caliber or someone similar make one to your specs. Then you actually get what you want rather than something close-ish.

 

[alamo5000]

I am planning on building a 6mm ARC with a 12ish barrel too. Who‘s barrel were you planning on using? The only one i can find online is the Faxon 12.5”

I have no idea yet. I'm just window shopping now. I have a 24" custom barrel in the works now. After I get that done I will look at a short upper. I already have a few SBR lowers so I'm interested in how the ARC compares to the 6.8 SPC.

A short barrel is possible but still away off for me.

I would tend to agree with Tony about getting a custom barrel made.

 

[ormandj]

I am wondering if anyone can direct me to any short barrel results others may have gotten.

If you have seen any velocity data for lighter to midweight bullets in a 12ish inch barrel I am curious to see it.

Hornady has velocity data for heavy bullets in a 12" barrel but that's all I have ever seen.

Check my older posts in this thread, I have posted Labradar data from my 10.5” 6ARC a few times with factory 108.

 

[alamo5000]

Check my older posts in this thread, I have posted Labradar data from my 10.5” 6ARC a few times with factory 108.

Cool. I will do that. The data I hope to run across will be the 50 to 90 grain range. I think the ARC could wind up working well in that role of short barrel action.

 

[SBRSarge]

There is a pending group buy on the 65Grendel forum for 12 inch 6ARC barrels. They are Green Mountain blanks and previous offerings have been well received.

There is also a 20 inch group buy going on now.

I think the barrels are around $160 or so.

 

[godofthunder]

Well, unfortunately I'll be sending my BA barrel back to BA for review. It's beating the shit out of my brass and accuracy is well outside of their sub-MOA guarantee. I'll post up some pictures of my brass when I get the chance.

I bought two BA barrels at the same time, one for me and one for my dad, and my dad's seems to be shooting great and is fine on brass. I'm hoping that BA can get this turned around quickly as I have some coyote hunting planned that I really want to use it for.

 

[BoDuke80]

Starting torque will depend on a number of factors about the barrel and muzzle device. What are the details? I can give a recommendation for a starting point but, it would be just that, a starting point. I did misunderstand, timing w/shims to align the hand guard to the barrel nut shouldn't cause an issue.

As far as barrel extension to upper fit, that depends on just how loose it is. If there is a lot of slop to take up, you can use some shimming material. I try to avoid uppers that fit this loose if at all possible. It's somewhat of a hassle to deal w/the shimming material if you ask me. Over the years we've also built the extension up and then turned it on a lathe until it fit snugly then bedded with some Loctite 620. Truth be told, as long as the upper isn't really loose, bedding w/Loctite 620 has yielded results that are just as good. The trick is to avoid a really loose upper if you can (this may be easier said than done, especially in the current market).

Permatex makes high temp sleeve retainer usually available at your local NAPA. Works just the same as the LT620. In case anyone can't find the Locktite.

 

[Yondering]

Well, unfortunately I'll be sending my BA barrel back to BA for review. It's beating the shit out of my brass and accuracy is well outside of their sub-MOA guarantee. I'll post up some pictures of my brass when I get the chance.

I bought two BA barrels at the same time, one for me and one for my dad, and my dad's seems to be shooting great and is fine on brass. I'm hoping that BA can get this turned around quickly as I have some coyote hunting planned that I really want to use it for.

Are you sure the rifle isn’t just over gassed?

 

[godofthunder]

Are you sure the rifle isn’t just over gassed?

Yeah, running and AB and have it set for 3:30 ejection. Brass is getting damaged when cycling the CH manually as well as after firing, leading me to believe it is chamber and/or barrel extension related. I'll post pics after my lunch.

 

[BoDuke80]

Yeah, running and AB and have it set for 3:30 ejection. Brass is getting damaged when cycling the CH manually as well as after firing, leading me to believe it is chamber and/or barrel extension related. I'll post pics after my lunch.

If one of you issues is bent case mouths that's a common issue with the Grendel. I would think it would transition to the arc. I put a small patch of the soft side of velcro on my shell deflector and it stopped that issue

 

[RMB]

II shoot a 6MM Grendel and had the same issues. I added an adjustable gas block and velcro and the problem was solved.

 

[Nick Danger]

I would love to convert one of my A.R. 15‘s to a 6 mm arc. But you can’t find any parts anywhere as of today. Same with ammo you can’t buy match grade you can’t buy parts and components what’s a guy supposed to do?