New 6mm Advanced Rifle Cartridge

About to pop my cherry on a 6ARC. I do run and gun shit so absolute accuracy and MV is not as important as a package that shoots about MOA and is handy over 3-8 miles.

Pulling down my 14.5” intermediate gas upper and replacing with a Noveske Afghan 14.5, will have a P&W Surefire three prong and if I run a can it’ll be a 7.62 RC2.

Have some Duramags on the way as well as 4 different bullets, from 95gr to 107.

Leaving brass along a course is gonna suck,,, but I think this may be a little advantage in the DMR style R&Gs without going to the weight and recoil of a large frame. We’ll see..


If I like it, will probably wear a 4-16x42 ATACR eventually. Will start with either the G3 1-10 that’s on it now or I’ll move a 3-15 NXS F1 over, though that gonna be choncky with a red dot up top .
 
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About to pop my cherry on a 6ARC. I do run and gun shit so absolute accuracy and MV is not as important as a package that shoots about MOA and is handy over 3-8 miles.

Pulling down my 14.5” intermediate gas upper and replacing with a Noveske Afghan 14.5, will have a P&W Surefire three prong and if I run a can it’ll be a 7.62 RC2.

Have some Duramags on the way as well as 4 different bullets, from 95gr to 107.

Leaving brass along a course is gonna suck,,, but I think this may be a little advantage in the DMR style R&Gs without going to the weight and recoil of a large frame. We’ll see..


If I like it, will probably wear a 4-16x42 ATACR eventually. Will start with either the G3 1-10 that’s on it now or I’ll move a 3-15 NXS F1 over, though that gonna be choncky with a red dot up top .
Noveskes DDF barrel is lighter than the afghan if that’s important to you. I imagine they’ll go on sale again Labor Day.
 
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I picked up CATs 6arc can to dedicate to mine and love it. Shot at a local indoor range yesterday with it and had zero gas to the face, and sounded great when Ive shot it outdoors as well. 18” rlgs with a5h2 and springo green spring it shoots very smooth
Yep, I run a CAT Noah Ti on my main 6 ARC and it's pretty great in that application for gas and suppression. My B&T RBS 762 also does well with the little ARC.
 
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Opinions please. Rifle is upside down in pic. Installed this mlok pic rail for the bipod mount. Seems to be minimal clearance between the mlok screw and gas block. With the bipod installed if I push down on the barrel only I can feel it make contact, but without pressure there’s no contact. Is this going to be an issue, or do I need to grind the screw down or move the mount altogether?
 

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Opinions please. Rifle is upside down in pic. Installed this mlok pic rail for the bipod mount. Seems to be minimal clearance between the mlok screw and gas block. With the bipod installed if I push down on the barrel only I can feel it make contact, but without pressure there’s no contact. Is this going to be an issue, or do I need to grind the screw down or move the mount altogether?
I’d move the mount or get a shorter screw
 
Opinions please. Rifle is upside down in pic. Installed this mlok pic rail for the bipod mount. Seems to be minimal clearance between the mlok screw and gas block. With the bipod installed if I push down on the barrel only I can feel it make contact, but without pressure there’s no contact. Is this going to be an issue, or do I need to grind the screw down or move the mount altogether?
Looks like you can loosen the mlok screws and slide the pic rail forward a little and then tighten it back down.

Just fyi, I have started running my bipods a little further back on the rail of my gas guns(toward the receiver)and I still get great stability but have noticed slightly less deviation on target than running the bipod all the way out toward the muzzle.
 
Opinions please. Rifle is upside down in pic. Installed this mlok pic rail for the bipod mount. Seems to be minimal clearance between the mlok screw and gas block. With the bipod installed if I push down on the barrel only I can feel it make contact, but without pressure there’s no contact. Is this going to be an issue, or do I need to grind the screw down or move the mount altogether?
You can use a 7 slot pic rail and completely bridge over the gas block. Its what I ended up doing to make sure no contact.
 
Finally got the X-Caliber 13", mlgs lightweight barrel that I ordered back in March in. Going to try a BFK Mod 0 thermal fit upper and reuse a 12.7" Aero handguard I have on this one. Waiting for Rexus Ultra bolts to come back in stock in the next few weeks and should be in business.

View attachment 8728232

Finally got the parts painted up with Alumahyde and put together this weekend, and a Rexus Ultra bolt on the way. I will say the BFK upper was a bit too interference fit with my barrel, even freezing the barrel and lightly torching the receiver threads, the rubber mallet had to put in some work to get the barrel in far enough that I could fully seat it with the barrel nut.

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Finally got around to shooting the GFR. TLDR: Gun shoots great, I failed it in preparation and execution lol. I started out standing off a tripod because I haven’t had much time to bushog around here, and groups were moa+. Decided to try prone and things got a lot better until I realized the ammo was sitting in the sun in 96 degree heat and the suppressor had come loose. Shots 15-19 with factory 103 Eldx in the first pic. First shot went way high and that when I found the can issue and the ammo issue. Let things cool down and 16-19 went much better, then 2 more a few minutes later to confirm. The shot on the right in the second pic was shot 1 of the day after bore sighting.

Overall I’m impressed with this thing so far. Need to stretch it out some and get it bloody!
 

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Mulling over switching my current 20" barreled 6.5 grendel AR-15 to 6mm ARC. From what I gather the brass can be sized down to 6mm ARC? Looking to do a 18-20" barrel threaded for a brake and prefer heavy profile but fluted. Is it worth switching as I currently reload and have all the dies and brass for 6.5 grendel. What barrels are available for the $500-$700? I'll want to buy a matched barrel and bolt. Thanks
 
Mulling over switching my current 20" barreled 6.5 grendel AR-15 to 6mm ARC. From what I gather the brass can be sized down to 6mm ARC? Looking to do a 18-20" barrel threaded for a brake and prefer heavy profile but fluted. Is it worth switching as I currently reload and have all the dies and brass for 6.5 grendel. What barrels are available for the $500-$700? I'll want to buy a matched barrel and bolt. Thanks
Is it worth switching for what reason?
 
Mulling over switching my current 20" barreled 6.5 grendel AR-15 to 6mm ARC. From what I gather the brass can be sized down to 6mm ARC? Looking to do a 18-20" barrel threaded for a brake and prefer heavy profile but fluted. Is it worth switching as I currently reload and have all the dies and brass for 6.5 grendel. What barrels are available for the $500-$700? I'll want to buy a matched barrel and bolt. Thanks
Check out Patriot Valley Arms AR barrels. 6 ARC , they will flute it for you and you can get a matched bolt. Not sure about the "HEAVY" profile though.
 
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Mulling over switching my current 20" barreled 6.5 grendel AR-15 to 6mm ARC. From what I gather the brass can be sized down to 6mm ARC? Looking to do a 18-20" barrel threaded for a brake and prefer heavy profile but fluted. Is it worth switching as I currently reload and have all the dies and brass for 6.5 grendel. What barrels are available for the $500-$700? I'll want to buy a matched barrel and bolt. Thanks
Craddock RTR. .875 gas journal. Or Bartlein but that would likely exceed your budget have a longer wait. My experience with 3 RTR barrels, 18 and 22” has been excellent. But agree with supercorndog - for what reason?
 
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Here are links to a variety of 6 arc ar barrels
 
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McGowan built barrels are hot garbage.
My 25 Quartermoor shoots great. I have read varying opinions on here and seem inconsistent barrels.
Also read the same on Shaw but again, I had a 6 ARC that was very accurate and consistent with 5 and 10 round groups. Only sold it to get a Proof CF, which frankly, isn’t anymore accurate. Or at least I’m not.
 
No need to play he said she said. Show me pictures of McGowan's threads. Show me pictures of their machine work.

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And they made three of those barrels like that for me. I still have two of them under my bench. And those were replacement for a used barrel I bought of theirs that had out of spec threads on both ends. So that's 4.

And I have an ar15 barrel from them with similar looking muzzle threads and the indexing pin on the barrel extention stuck up about 1/4" past the lip. It shoots good though. Kinda scary to wonder if the thread interface with barrel extention is safe. So that's 5. I saw one in the PX with threads like mine and asked when it was built and it was 2019 or 2020. So that's 6, built over a 5 year time frame.
 
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Is it worth switching for what reason?
I have a 6.5 grendel I put together in about 2017 and I'm pretty sure the throat is worn out. I used to run 123sst's in it pretty hot and nowI run Sierra TMK 107 handloads. It gradually stopped grouping nicely so I'm going to swap the barrel out. Current is a barrel and bolt from Faxon, 416r 5r fluted and black nitrided. I use that one for out to 750 and may try some local gas gun matches that run 1100 max. Trying to get as good of precision as I can for that price range. Heavy profile isn't mandatory but don't want pencil.
 
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Here are links to a variety of 6 arc ar barrels
Man what a list! Thanks. The Craddock looks like a good fit based on options.
 
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I have seen factory savages with rail road track rifling shoot better than that. And I wouldn't recommend a factory savage barrel either. The machine work is going to be better than anything McGowan turns out though.
Shoot better than what? 0.732 MOA. Ok cool guy. Just because your barrels are shit paperweights, that for some reason you’re still holding on to, doesn’t mean they all are. That’s the point.
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Shoot better than what? 0.732 MOA. Ok cool guy. Just because your barrels are shit paperweights, that for some reason you’re still holding on to, doesn’t mean they all are. That’s the point.
View attachment 8754567
Yes, shoot better than 3/4 moa. Consistently, like the dudes that owned them would have cropped that group out of the picture, not cherry picked it. 🤣🤣

You didn't make a point. You continued to play he said she said.

So those pictures of their machine work....🙈🙉🙊
 
Yes, shoot better than 3/4 moa. Consistently like the dudes that owned them would have cropped that group out of the picture, not cherry picked it. 🤣🤣

You didn't make a point. You continued to play he said she said.

So those pictures of their machine work....🙈🙉🙊
Who gives a shit what the lands look like if the barrel shoots. You apparently. There’s threads and threads on long range hunting and here with plenty of anecdotal stories that have had positive experiences. Many where they felt the barrel had some internal flaws. Ultimately, they too didn’t give a shit because the barrel shot great. Your anecdotal story and barrel pics don’t equate to shit in the tens of thousands of barrels probably that McGowan has produced. 😉
 
Who gives a shit what the lands look like if the barrel shoots. You apparently. There’s threads and threads on long range hunting and here with plenty of anecdotal stories that have had positive experiences. Many where they felt the barrel had some internal flaws. Ultimately, they too didn’t give a shit because the barrel shot great. Your anecdotal story and barrel pics don’t equate to shit in the tens of thousands of barrels probably that McGowan has produced. 😉
Internal flaws. 🤣🤣🤣

Probably produced. 🤣🤣🤣

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