New 6mm Advanced Rifle Cartridge

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?
If you look you can find the stuff you need. This is basically all you need to convert and it took me just a couple minutes to find. I just put two together recently.



 
If you look you can find the stuff you need. This is basically all you need to convert and it took me just a couple minutes to find. I just put two together recently.



I have to admit that was fast... can ya do the same with ammo and components that are in stock and that doesn't cost too much? Before all this mess i was reloading 300 win mag for about $0.74 with new brass, i guests those days are over... thx again for the info.
 
DANG! I missed the leverloution! But I found some other powders:
Shooters World Match Rifle - looks good for 6ARC
Shooters World Precision - looks good for 6ARC
Shooters World SW4350 - Garand snaks
IMR 4451 - Garand snaks
Also have some CFE223 to try, but that may get used for ACTUAL 223 (Which I'm not gonna waste my time/primers on now that I have ARC)

I'm running Berger 105s out of 20" barrel

Thoughts on which I should start with?
 
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Get 6 ARC dies, 6.5 Grendel brass, get a Lee 6.5 Grendel case trimmer for the holder and a Lee 6mm PPC gauge (trim with a file to produce 1.490 case length), just about any 6mm bullet (see the 2021 Hodgdon reloadng manual) and go forth.

I get once fired 6.5 Grendel from the range because none of those folks reload.

this ain’t hard.
 
Get 6 ARC dies, 6.5 Grendel brass, get a Lee 6.5 Grendel case trimmer for the holder and a Lee 6mm PPC gauge (trim with a file to produce 1.490 case length), just about any 6mm bullet (see the 2021 Hodgdon reloadng manual) and go forth.

I get once fired 6.5 Grendel from the range because none of those folks reload.

this ain’t hard.
It is if you go looking for range brass after I been there😁
 
...just a quick question for the more experienced reloaders; been seeing posts about converting AK 7.63x39 brass to 6ARC and was wonder has anyone here done it yet and what kind of issues (if any) did you encounter? What were your results like?

...my attempts at getting components or ammo have been futile and I don't expect it to improve anytime soon (hopefully not a 4 year period :sneaky: )so I've been searching for alternatives to at least start something...
 
...just a quick question for the more experienced reloaders; been seeing posts about converting AK 7.63x39 brass to 6ARC and was wonder has anyone here done it yet and what kind of issues (if any) did you encounter? What were your results like?

...my attempts at getting components or ammo have been futile and I don't expect it to improve anytime soon (hopefully not a 4 year period :sneaky: )so I've been searching for alternatives to at least start something...

I've converted a fair amount of x39 to Grendel and 243 LBC. It takes some work but isn't too bad with the right brass, when components were available. Given the lack of primers available now though, I'd have to seriously question the logic of converting any significant quantity, but you can make some cheap fireforming loads that will cycle the action and shoot reasonably well.

Be aware though, most x39 brass I've used is capable of handling even less pressure than Grendel brass; primer pockets open quickly at pressure & velocity that good Grendel brass will handle 5-6 reloads easily.

Don't bother with newer S&B x39 brass, I've got a bunch but the primer pockets aren't deep enough for rifle primers. PMC & PPU seem to be the best bets in my experience, but 3-4 loadings is about it for full power loads.

There is a current thread on the 6.5 Grendel forum about this exact topic that you might find useful.

You're much better off finding some Grendel brass somewhere, even range pickup, and using that.
 
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.
Still no pics but that mostly sounds like just some sharp edges on the barrel extension lugs, which is pretty common and really easy to fix. You can see the edges that need to be smoothed if you extract the round slowly; just rub those edges with some emery cloth or strip of sandpaper to break the sharp edge, and make sure to clean up the grit afterwards. It’d take you longer to box it up to ship back than to just fix it.

Also FYI the 3:30 ejection pattern isn’t necessarily ideal for non-223 cases; ejection pattern changes with different case shapes so it’s better to tune based on last round bolt lock than ejection direction.
 
Is making 6mm arc brass out of grendel as easy as running it though the correct die and trimming to length?
I can find grendel brass today, arc brass not so much. Looking to build a little deer rifle for my kids
 
Tried some new powder today SW Precision. Didn't get chrono data today. saw pressure signs on the last ladder load.
ATN sighted in at 200yds and clays are poof/gone.

As for the question about brass, yes, the conversion is easy, just size and trim back a bit.
SWprecisionLoads.jpg


 
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.
I have the ATN 4k 3-14 on a 12" Grendel Pistol and with Ballistics entered I've paired with the ATN Rangefinder and ranged a 12" plate at 450 yards then put five outta five on it. It works. Also I've had better Performance hanging the IR under the front of the Barrel I went with a Sniperhogg 66 LRX. See GOOD out to 400 yards or so.
 
Natches has lots of powders in stock now. just scored 4lbs of 748 (not related to this rifle but seems relavant).
Still drooling for leverloution and hard primers.

As for the illuminator, I am working on a mount to put it on the underside of the rail.
The game warden said yote hunting only allows for hunting while other game animals are in season and with those firearms. Doh!
May switch back to turrkey hunting.
 
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Still no pics but that mostly sounds like just some sharp edges on the barrel extension lugs, which is pretty common and really easy to fix. You can see the edges that need to be smoothed if you extract the round slowly; just rub those edges with some emery cloth or strip of sandpaper to break the sharp edge, and make sure to clean up the grit afterwards. It’d take you longer to box it up to ship back than to just fix it.

Also FYI the 3:30 ejection pattern isn’t necessarily ideal for non-223 cases; ejection pattern changes with different case shapes so it’s better to tune based on last round bolt lock than ejection direction.
 

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Natches has lots of powders in stock now. just scored 4lbs of 748 (not related to this rifle but seems relavant).
Still drooling for leverloution and hard primers.

As for the illuminator, I am working on a mount to put it on the underside of the rail.
The game warden said yote hunting only allows for hunting while other game animals are in season and with those firearms. Doh!
May switch back to turrkey hunting.
See your in middle Tn, Shooters Sporting Goods in Camden Tn had Leverloution $30 a lb last time I was in there I grabbed a couple lbs. Be prolly an hour drive for ya.... Might be worth a call see if they still got it.
 
LVR 1 lb cans at Midsouth:


I tried some LVR in my Grendel (still waiting on ARC parts) this weekend, picked up ~ 100fps over my warm Ar-Comp loads with no pressure signs, can't wait to try it in the ARC. Sure was dirty though, I probably need to turn the gas down a bit, but still.
 
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Thanks for the tip on Shooter Sports in Tn, Thats about 2.5 hours from me actually. Would be worth it for 8lbs!
There's a couple other places around here in Cullman AL that I would check before driving that far.
Midsouth is already out of LeverLoution. Weird because I checked just this morning must have missed it again.
 
Other end of TN...Johnson city Mahoneys had varget, lever and lots of other stuff this past week and is getting things somewhat weekly (just no bullets at all...) They are limiting to 2lbs and 200 primers however. They did raise prices somewhat I think I paid $37 for each lb of varget and $8 per 100 federal match primer.
 
LVR 1 lb cans at Midsouth:


I tried some LVR in my Grendel (still waiting on ARC parts) this weekend, picked up ~ 100fps over my warm Ar-Comp loads with no pressure signs, can't wait to try it in the ARC. Sure was dirty though, I probably need to turn the gas down a bit, but still.
I found the same damn thing!! I run a can on everything I shoot so of course I am using it during load development and that is exactly what I have found. I started off with both CFE and Leverevolution and found that my gun got really carbon fouled in less than 100rds. I had some decent loads with it but I found that Varget shot really well in mine too!! I didn't actually loose that much in velocity with the varget so I am just going to stay with it. Mine is just a hammer with several loads from 85 to 108s. My issue now is it is really tearing up my brass!! I am getting ejector marks and "Swiping" on my case heads. However the damn primer is not even pitted or flattened. I looks just like it did when I pressed it in. I am also using loads that are recommended by Hornady......
 
Thanks for the tip on Shooter Sports in Tn, Thats about 2.5 hours from me actually. Would be worth it for 8lbs!
There's a couple other places around here in Cullman AL that I would check before driving that far.
Midsouth is already out of LeverLoution. Weird because I checked just this morning must have missed it again.
My mistake, I binge read pretty much all 34 pages of this forum post and by the end things got a little fuzzy !!
 
I found the same damn thing!! I run a can on everything I shoot so of course I am using it during load development and that is exactly what I have found. I started off with both CFE and Leverevolution and found that my gun got really carbon fouled in less than 100rds. I had some decent loads with it but I found that Varget shot really well in mine too!! I didn't actually loose that much in velocity with the varget so I am just going to stay with it. Mine is just a hammer with several loads from 85 to 108s. My issue now is it is really tearing up my brass!! I am getting ejector marks and "Swiping" on my case heads. However the damn primer is not even pitted or flattened. I looks just like it did when I pressed it in. I am also using loads that are recommended by Hornady......
You’re getting case head marks because your Varget loads are way higher pressure than the same results with Lever.

It seems that several of you are missing the importance of restricting the gas if you’re using Lever, especially if you’re shooting suppressed. Lever produces a lot more gas and the rifle needs to be tuned accordingly, otherwise it’ll be overgassed with all the issues that causes.
 
You’re getting case head marks because your Varget loads are way higher pressure than the same results with Lever.

It seems that several of you are missing the importance of restricting the gas if you’re using Lever, especially if you’re shooting suppressed. Lever produces a lot more gas and the rifle needs to be tuned accordingly, otherwise it’ll be overgassed with all the issues that causes.
I have an adjustable gas block on it. I set it so it was throwing brass at 3:30. It was doing it with lever and CFE too. Are you saying I am still over gassed??? My load is 29.5 of Varget with an 87gr. Hornady says that is a safe load for pressure. Will cranking down the pressure on my can take away the brass hammering??? Thanks for the reply!!!
 
I have an adjustable gas block on it. I set it so it was throwing brass at 3:30. It was doing it with lever and CFE too. Are you saying I am still over gassed??? My load is 29.5 of Varget with an 87gr. Hornady says that is a safe load for pressure. Will cranking down the pressure on my can take away the brass hammering??? Thanks for the reply!!!
Forget the ejection direction, it’s not a 223. Adjust it based on last round bolt hold open, plus a little more (1/8-1/4 turn) for reliability. If you add a suppressor it’s definitely going to be over gassed unless it’s tuned with the suppressor on it.

Also, if the rifle will cycle with Varget, it’ll be over gassed with a full charge of Lever, so no surprise there if it seems dirty. And you’re shooting suppressed which will always be dirty anyway.

But my main point was that if you’re pushing Varget up near Lever velocities, then you’re pushing the pressure pretty high. There’s no getting around that; Lever is significantly faster than Varget at similar pressure.
 
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Forget the ejection direction, it’s not a 223. Adjust it based on last round bolt hold open, plus a little more (1/8-1/4 turn) for reliability. If you add a suppressor it’s definitely going to be over gassed unless it’s tuned with the suppressor on it.

Also, if the rifle will cycle with Varget, it’ll be over gassed with a full charge of Lever, so no surprise there if it seems dirty. And you’re shooting suppressed which will always be dirty anyway.

But my main point was that if you’re pushing Varget up near Lever velocities, then you’re pushing the pressure pretty high. There’s no getting around that; Lever is significantly faster than Varget at similar pressure.
Of course this is assuming you’re sizing correctly for minimal shoulder bump rather than just cranking the die down to the shell holder. Excessive shoulder setback can cause case head marks too.
 
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Look at your ejector pin, does it have a tapper cut or rounded on the edge were it contacts the case head. I had the same problem and the ejector had a sharp edge on it. Basically it was a straight cut with a sharp edge and it was cutting into the case head. After I rounded it off it stopped doing it.

I chucked the pin in a drill and used a small file to re-profile it and then polished it with 1000 and 1500 grit sandpaper. No more swipe marks and no more brass chips in the bolt. I had this problem with all three of my 6 ARC's and they all had the sharp edge on the pin.

Light swipe marks is considered normal in some guns, that is if you run your finger nail over it and it does not catch a burr.
 
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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 don’t have any numbers for factory 6 ARC ammo, but can share a comparison of a warm load of Lever under the 90gr TGK in my 243 LBC barrels:

24” - 3160 fps
19” - 3055 fps
12” - 2795 fps

I haven’t loaded any 70gr ammo in a while but when I do I can run a back to back comparison and share those results too.
 
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Forget the ejection direction, it’s not a 223. Adjust it based on last round bolt hold open, plus a little more (1/8-1/4 turn) for reliability. If you add a suppressor it’s definitely going to be over gassed unless it’s tuned with the suppressor on it.

Also, if the rifle will cycle with Varget, it’ll be over gassed with a full charge of Lever, so no surprise there if it seems dirty. And you’re shooting suppressed which will always be dirty anyway.

But my main point was that if you’re pushing Varget up near Lever velocities, then you’re pushing the pressure pretty high. There’s no getting around that; Lever is significantly faster than Varget at similar pressure.
Bingo!! you hit the nail on the head with sizing!! When I first started shooting the rifle I had made my brass from 6.5 Grendel brass. When doing load testing after around 50 or so rounds down the barrel I started getting 'Failure to fire" it would chamber but not go off. I chalked it up to the rifle being dirty and also that my brass was on the very edge of fitting the chamber. SOooo I resized all of my brass to make sure this was not an issue in the future when the rifle started getting dirty. NOW, my question is with correctly sized brass and a correctly adjusted gas block, will this solve my pressure issues??? Can I expect to stay within safe pressures following Hornadys recommended loads?? This damn thing shoots so well with this load I hate to have to change it!!! Thank you so much for your input on my problem and Dino I will check my ejector as you suggested. Thanks to you both!!
 
If you are following Hornady load data you are not over pressured. Their loads are on the conservative side. Light swipe marks are not always indicative of over pressure. Some rifles just do it. And I have three ARC's and they all did it untill I modified the ejector pin. I was also getting brass flakes in the bolt head. I reload almost all the ammo I shoot, very rarely do I shoot factory stuff unless I want some brass to reload with. I am going through that process right now as I have obtained another 6mm Arc in a bolt action. I want virgin brass that is dedicated to this particular gun and has not been fire through one of the DI rifles.
 
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Took my 18” Odin out to the range braving the almost-freezing temps and howling 30mph gusting to 40 winds. Had to do something to pass the time while the beef briskets from my thread in Maggie’s Drawers were smoking.

The center group 3” above the diamond is my first five of the day. I adjusted 3moa down, then shot top left, top right, bottom left and bottom right. I was using the ELD-M and Black as noted by each target. The randon four rounds just right of center are from a 5.56 I was playing with.

Top left group chrono’d at 2621, I just neglected to write it on the target.

All groups were benched at 100yds.

DB9A4271-6919-418D-AED6-33C620FB0BC3.jpeg


Barrel had ten rounds through it before today.

I wish I had saved the S.D. from the bottom right group that strung vertically.

I wish I always shot like the bottom left!

The rifle;
-Odin 18” thermo fit into a BCM upper
-SiCo Omega direct threaded
-Coda Evolution hand guard
-Trijicon AccuPower 4-16 in Warne rings
-Detroit Gun Works lower
-STR stock
-Larue flat bow MDT trigger


9ADF69E0-902A-49E2-952F-4DB4252E4D2B.jpeg


I think I’m gonna like this rifle. It shot easy and the Omega yielded a nice mellow ‘poonk’ sound.
 
so what are the go to powders for the 6mm ARC? finally found some small rifle primers today at Midway USA. Have a shit ton of 6.5 grendel brass that im going to use. now just need to order some powder
 
Bingo!! you hit the nail on the head with sizing!! When I first started shooting the rifle I had made my brass from 6.5 Grendel brass. When doing load testing after around 50 or so rounds down the barrel I started getting 'Failure to fire" it would chamber but not go off. I chalked it up to the rifle being dirty and also that my brass was on the very edge of fitting the chamber. SOooo I resized all of my brass to make sure this was not an issue in the future when the rifle started getting dirty. NOW, my question is with correctly sized brass and a correctly adjusted gas block, will this solve my pressure issues??? Can I expect to stay within safe pressures following Hornadys recommended loads?? This damn thing shoots so well with this load I hate to have to change it!!! Thank you so much for your input on my problem and Dino I will check my ejector as you suggested. Thanks to you both!!
There’s no way for the rest of us to say for sure what your rifle is doing or will do with those loads. Sure, this Hornady data is generally on the mild side, but you can still run into an over pressure situation, especially if you’re getting high velocity out of Varget; the data is intended to be safe in most barrels but there’s a reason every manual says to work up your own loads.

Light case head swipes are one thing, being caused by early unlocking of the bolt, but if there are actual impressions in the case head, that indicates pressure or headspace. I don’t like that a couple guys here are telling you it’s no big deal and normal; that’s making some big assumptions that your comments don’t justify. It might be fine, but it might not be; you haven’t given enough info to say for sure.
 
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I have always watched for pressure
There’s no way for the rest of us to say for sure what your rifle is doing or will do with those loads. Sure, this Hornady data is generally on the mild side, but you can still run into an over pressure situation, especially if you’re getting high velocity out of Varget; the data is intended to be safe in most barrels but there’s a reason every manual says to work up your own loads.

Light case head swipes are one thing, being caused by early unlocking of the bolt, but if there are actual impressions in the case head, that indicates pressure or headspace. I don’t like that a couple guys here are telling you it’s no big deal and normal; that’s making some big assumptions that your comments don’t justify. It might be fine, but it might not be; you haven’t given enough info to say for sure.
I have always watched for pressure signs by watching my primers. I have been reloading for longer than I care to remember but I am fairly new to the ARs. I had one jam up on me in Nam and I hated the damn things for years and would have nothing to do with them. My son is in the NG and used to shoot on the All Guard Team. He was out here on vacation shooting with me and had brought his AR. He was shooting it at 600yds and I could not believe how well it shot. So after playing with it I got interested in them again and just used them for prairie dogs. Then my son in laws started shooting long rang comps where you need to shoot long range rifle, AR and pistol. So then we started building our own. With all my bolt guns, as I said, I always watched my primers. When I started to get a "Spur" I knew I was damn close to getting pressure. When it flattened it was either an oversized case of pressure, when I got a stiff bolt lift, time to quit and pull some bullets. The thing with this is my primers look just like the factory ammo I have shot. No spur, no flattening. I honestly feel right now that I have two issues. One is I have oversized my brass to the point of it may be junk and two I think I am over gassed. We have a couple of inches of snow on the ground now but I may go out and shoot it just to see If I can get the right adjustment for the can by using the lock back method instead of the brass timing. I will shoot it with and without the can too to see if that is an issue and will keep you posted. My problem is all my brass is probably way undersize right now. I will load a few once fired factory cases with the die reset.. Will keep you posted and once again thank you for the reply. If you need any more info please ask away.....
 
I just got in from the range. I test fired the rifle without the can and with the can. I found that I was over pressure with the can on it. I had to close it up about 5 clicks. When I shot it without the can on it the brass appeared pretty much normal. Every once in awhile I would get a faint ejector mark but this was also the same thing I was getting with factory. Now with the can, I am still getting ejector marks on my brass and some swiping, but nothing like before but still doing it. I will drop my load a half grain and see if that makes a difference. Thanks for all the tips guys appreciate all the suggestions!!!
 
No good, or just don't like them? I've never used one of those.
They worked fine but I used them with bolt guns on XLR chassis and I had to pull the stock off the buffer tube after every range trip so I could get the bore guide and cleaning rod to clear the stock. Got to be a pain so I switched them all to Magpul PRS stocks. Shouldn't be a problem with gas guns.
 
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They worked fine but I used them with bolt guns on XLR chassis and I had to pull the stock off the buffer tube after every range trip so I could get the bore guide and cleaning rod to clear the stock. Got to be a pain so I switched them all to Magpul PRS stocks. Shouldn't be a problem with gas guns.
i'm also looking for one if you are interested in getting rid on one.