New 6mm Advanced Rifle Cartridge

#201
toygunner said:
I think anything shorter than 20” is giving up too much burn time/velocity for any of the smaller caliber grendel
Variants . My 20” 22 grendel test barrel yielded good velocity with 75 elds
Click to expand...

Agreed 18” seems like it will be good for the ARC. My 12.5” grendel gets 2300fps with 123gr SST and considering the length of the gun to terminal performance i am not sure there is a better option for its intended purpose. For which is hog hunting but it is just incredibly versatile for a 12.5" gun.
 
  • Like
Reactions: JS8588
#203
I am happy to see someone finally standardized one of the 6mm Grendel wildcats, although they way they did it, it will chamber quite nicely in the Grendel chamber. I bet a few people will do that.

I have been shooting 6.5Grendel pretty much since it came out and it is easily my favourite general purpose AR cartridge. Part of the reason for that is the fact that it does quite well out of a moderate length barrels. The sweetspot seems to be right around 18", although 16" barrels work well too. My 18" barrel is technically a 264LBC chamber, not that it matters much. I am getting about 2520fps with Hornady factory 123gr loads.

I might build a 6mm ARC, but I will wait until there are some reports of what velocities people are getting out of 16" or 18" barrells. That 2700fps number seems to be with a 24" tube. If it drops into the 2550fps range out of an 18" barrel, I'll stay with the 6.5.

Anyway, after the 224V introduction nonsense, I am not itching to be an early adopter for now.

ILya
 
  • Like
Reactions: jetsurgeon, Rebels010, JS8588 and 3 others
#204
2700fps from a 20" barrel with a 108gr ELD M from the looks of it.. Not bad at all. 18" is going to be perfect for a SPR that is maneuverable. I was thinking i was going to go Valkryie but proof and a mk5 with this little cartridge would be a very nice SPR.
 
  • Like
Reactions: MSTN
#205
Barrett just posted this:

𝗕𝗔𝗥𝗥𝗘𝗧𝗧 𝗔𝗡𝗡𝗢𝗨𝗡𝗖𝗘𝗦 𝗦𝗛𝗜𝗣𝗠𝗘𝗡𝗧 𝗢𝗙 𝟲𝗠𝗠 𝗔𝗥𝗖 𝗥𝗜𝗙𝗟𝗘𝗦 𝗧𝗢 𝗨.𝗦. 𝗗𝗢𝗗

Barrett Firearms Manufacturing, Inc. is pleased to announce that it has partnered with Hornady Manufacturing to chamber the REC7 rifle series in the new 6mm ARC offering. The first production run of these rifles has already been delivered on time to the United States Department of Defense, fulfilling a contract that was awarded to Barrett late last year.

The combination of the proven REC7 DI gas system and the potent 6mm ARC cartridge creates a product that is consistently accurate and easy to shoot. Carrying 24 rounds in the magazine, the 106 gr. ELD Match bullets leave the 18” Proof Research match grade stainless steel or carbon fiber barrel at over 2650 fps. This easily gives the rifle supersonic capabilities past 1000 yards.

Barrett anticipates these rifles will be available to the US commercial market after all US Military deliveries have been completed.
 
  • Like
  • Love
Reactions: gozoogle, Lightning8, winniedonkey and 2 others
#206
5RWill said:
2700fps from a 20" barrel with a 108gr ELD M from the looks of it.. Not bad at all. 18" is going to be perfect for a SPR that is maneuverable. I was thinking i was going to go Valkryie but proof and a mk5 with this little cartridge would be a very nice SPR.
Click to expand...


I have not yet seen an ammo introduction where the manufacturers were not either mistaken about velocity or lying about velocity or paying some gunwriter to lie about velocity. And that's before we get to them saying nonsense about accuracy, barrel life, terminal ballistics, etc. I think I already saw somewhere that 6mm ARC offers better external ballistics and terminal ballistics than 308.

Best examples are 6.8SPC and 224V, but there are plenty more.

Once factory ammo is reasonable available and well explored, we'll see. I am not buying anything off of media blitzes with hand picked and hand made ammo. It is not uncommon for early hand picked loads to be running at higher pressure for better PR.

Now, given what we know about all the 6mm Grendel wildcats out there, I am much more hopeful about this cartridge than about most others I have seen introduced for a while, but I will still wait.

ILya
 
  • Like
Reactions: gozoogle, rjh, JS8588 and 3 others
#207
koshkin said:
I have not yet seen an ammo introduction where the manufacturers were not either mistaken about velocity or lying about velocity or paying some gunwriter to lie about velocity. And that's before we get to them saying nonsense about accuracy, barrel life, terminal ballistics, etc. I think I already saw somewhere that 6mm ARC offers better external ballistics and terminal ballistics than 308.

Best examples are 6.8SPC and 224V, but there are plenty more.

Once factory ammo is reasonable available and well explored, we'll see. I am not buying anything off of media blitzes with hand picked and hand made ammo. It is not uncommon for early hand picked loads to be running at higher pressure for better PR.

Now, given what we know about all the 6mm Grendel wildcats out there, I am much more hopeful about this cartridge than about most others I have seen introduced for a while, but I will still wait.

ILya
Click to expand...

Agreed, i have my doubts but i hope i'm proven wrong. I would love for this thing to somehow retain moderate velocity down to short configs in decent a 6mm weight class.
 
#208
Just talked to Forster and the engineer said they are looking at producing dies for the 6mm Arc. He asked for my information to use as interest for production. Would be a good idea if we dropped em a line and let them know how many would buy.
 
#210
koshkin said:
I have not yet seen an ammo introduction where the manufacturers were not either mistaken about velocity or lying about velocity or paying some gunwriter to lie about velocity. And that's before we get to them saying nonsense about accuracy, barrel life, terminal ballistics, etc. I think I already saw somewhere that 6mm ARC offers better external ballistics and terminal ballistics than 308.

Best examples are 6.8SPC and 224V, but there are plenty more.

Once factory ammo is reasonable available and well explored, we'll see. I am not buying anything off of media blitzes with hand picked and hand made ammo. It is not uncommon for early hand picked loads to be running at higher pressure for better PR.

Now, given what we know about all the 6mm Grendel wildcats out there, I am much more hopeful about this cartridge than about most others I have seen introduced for a while, but I will still wait.

ILya
Click to expand...

You really think Hornady is paying him to straight up lie on video about the velocities he chrono'd in his 20" AR, complete with a picture of his Lab Radar screen? All to what? Convince people that they will get 50 fps more than reality? I don't think so.

The barrel, being on the nicer end and probably lapped etc. might well be faster than a basic BA barrel, but I really doubt he's lying and Photoshopping chrono velocities.

108gr ELDs @ 2,650+ fps out of an 18" barrel (Barrett press release) sounds really good for factory ammo to me. 123gr ELD factory averages 2,390 fps out of my 16" Grendel, and my accuracy handload for 73gr ELDs (much lower BC) is running ~2,700 fps out of my 18" .223 Wylde.

Edit: Just found the Barrett press release, it actually says "over 2,630 fps" instead of "over 2,650 fps", not really a material difference for my uses.

News - Barrett Firearms

news.barrett.net news.barrett.net
 
Last edited:
  • Like
Reactions: yellowfin
#211
Gtscotty said:
You really think Hornady is paying him to straight up lie on video about the velocities he chrono'd in his 20" AR, complete with a picture of his Lab Radar screen? All to what? Convince people that they will get 50 fps more than reality? I don't think so

The barrel, being on the nicer end, might well be lapped and faster than a basic BA barrel, but I really doubt he's lying and Photoshopping velocities.

108gr ELDs @ 2,650+ fps out of an 18" barrel (Barrett press release) sounds really good for factory ammo to me. 123gr ELD factory averages 2,390 fps out of my 16" Grendel, and my accuracy handload for 73gr ELDs (much lower BC) is running ~2,700 fps out of my 18" .223 Wylde.
Click to expand...

I offered three options. You are looking at the last one.

I'd be very surprised if Tom is lying, but I would not be at all surprised if final production ammo turned out to be a bit different than the first batches of ammo used for the marketing push. It might not even be all that intentional: when you go into full production you have to stay further away from the hairy edge of performance.

There is already a marketing blurb that they have a "special" bullet with special construction better terminal ballistics than the 308. There is some word sophistry there, but they are basically lying. Whatever special design bullet they have, if they apply the same design to a larger bullet, it will have better terminal ballistics. Only professional marketing can make these claims with a straight face (half of my job is marketing; ask me how I know). So why would I assume they are not lying somewhere else?

If it can reliably push 108gr ELDs out of an 18" barrel with factory ammo at 2650fps, I will most certainly build a rifle in 6mm ARC.

ILya
 
  • Like
  • Love
Reactions: Jsp556, deersniper, Aescobar17 and 3 others
#214
What I was told at SHOT from my contact at Hornady was the development was done with Proof and in an 18" barrel for the DOD request. They may get a special round for their needs. I will ask my contact eventually but he is pretty busy given the current ammo demand, CV absentees and new product releases. I try to leave him alone as much as I can because he's busy working on new stuff. He mentioned they really focused on barrel life and terminal/barrier performance at the specified ranges that the DOD requested. I'm sure you could squeeze more hand loading for it.

I posted the relevant data a while back for velocity with the factory loaded ammo. I was immediately interested when we spoke at SHOT. He offered to loan me the chamber reamer they had made for a build a while back, but I just didn't have the extra cash to spend to build a new upper. Maybe later this year or next year. It sucks being a "poor" in CA.
 
  • Like
Reactions: waveslayer
#215
LAN TAC has posted velocity and energy charts of 18" as well as 14.5" barrels along with their marketing.

qtQZc90.jpg


KaIxw2N.jpg
 
  • Like
Reactions: slockwood
#216
koshkin said:
There is already a marketing blurb that they have a "special" bullet with special construction better terminal ballistics than the 308. There is some word sophistry there, but they are basically lying. Whatever special design bullet they have, if they apply the same design to a larger bullet, it will have better terminal ballistics.
Click to expand...

Sure, but it would be a .30 caliber bullet with the same characteristics, which in turn would mean that it would be too long and too heavy to be effectively used in a .308 Winchester chambering. It would be a bullet for .300 NM or something else in that ballpark.

It's an apples to oranges comparison, to be sure, but it's not lying. It is also the chambering that this new cartridge is supposed to supplant for the DOD contract they were developing it for, so you can't say it isn't relevant.
 
  • Like
Reactions: LRJammer
#217
Marketing - like what the Co's first advertised the 224 Valkyrie to achieve?! Then they figured out that loading it down was better than blown primers and ruined 1x brass.
I helped a guy experimenting with a wildcat that is basically a 224V, and the developer found out that at the time only SSA brass would handle higher pressures longer than the rest of the brands, so how strong the brass is makes a big difference.

Hornady brass is what it is and it's not Lapua, that's for sure.

I've pushed 6mmART40 to 2920 fps with 105's before in a 26" barrel for 1 firing, slowed it down to 2875 fps afterwards, and Lapua brass held up for 6-7 firings. Twice that amount slowed down to 2740 fps.

I won't say yay or nay at this point but Hornady better use strong brass and the perfect burn rate of powder.
 
#218
I hunted some with a 6ARC AR earlier this year. DOD spec Proof 18" barrel and Hornday 108 ELD-M. It was accurate and extremely soft-shooting.

Mags are the current issue, 6.5G mags are pretty bad all around and that's what is available currently.

Got this javelina at just over 400 yards. I didn't cut it open to see the damage, but it sure dropped it in it's tracks.
 

Attachments

  • Screen Shot 2020-06-03 at 1.10.21 PM.png
    Screen Shot 2020-06-03 at 1.10.21 PM.png
    2.4 MB · Views: 239
  • Like
Reactions: deersniper, MichiganMitten, schmi015 and 2 others
#219
joffe said:
Sure, but it would be a .30 caliber bullet with the same characteristics, which in turn would mean that it would be too long and too heavy to be effectively used in a .308 Winchester chambering. It would be a bullet for .300 NM or something else in that ballpark.

It's an apples to oranges comparison, to be sure, but it's not lying. It is also the chambering that this new cartridge is supposed to supplant for the DOD contract they were developing it for, so you can't say it isn't relevant.
Click to expand...

The statement that terminal ballistics are equal or better than the 308 is straight up lying.

If they said that the terminal ballistics of their special 6mm bullet are better than 147gr FMJ 308, I would be totally on board with that. The blanket statement is full of manure.

As far as the overall chambering goes, I am very much onboard with what they are trying to do and I hope this works as well as they claim. I do not like large frame semi-autos. That's how I ended up with the Grendel in the first place.

ILya
 
  • Like
Reactions: MichiganMitten, JS8588, Redfisher60 and 2 others
#220
M4guru said:
I hunted some with a 6ARC AR earlier this year. DOD spec Proof 18" barrel and Hornday 108 ELD-M. It was accurate and extremely soft-shooting.

Mags are the current issue, 6.5G mags are pretty bad all around and that's what is available currently.

Got this javelina at just over 400 yards. I didn't cut it open to see the damage, but it sure dropped it in it's tracks.
Click to expand...

I agree mags are the current problem... makes me wonder what mags the DOD is using and if they have found a solution
 
  • Like
Reactions: Constructor
#221
RTV said:
I agree mags are the current problem... makes me wonder what mags the DOD is using and if they have found a solution
Click to expand...

The Barrett press release says 24rd mags, and the mag in the photo looks E-Lander-ish. I've been using ASC 10 and 15 round mags with no problems, I didn't realize folks were having so many problems with the other brands, lucky I tried them first I suppose.
 
#223
lennyo3034 said:
I can't get ASC mags to feed for shit with my Grendel. Hoping Elander is better.
Click to expand...

For what its worth, I've had the opposite results. Mine are 10 rounders and I don't know if that has something to do with it, but they ASC feels like it might hold more (and seats on a closed bolt no problem) but my elanders are 9 rounders at best.
 
#224
I believe they were using E-Landers. Regardless of the gun (Barrett makes a good one) none of the mags are duty-ready, especially if any particulate is introduced.

The magazine roulette you guys are seeing play out above is typical, they're very inconsistent from mag to mag and lot to lot.
 
#230
Agree on PRI mags. No problems with mine.

I'll be first in line for a Howa mini 6ARC. I've got the 6 predator and think it would be tons of fun in a little Howa, but haven't gotten around to wanting a rebarreling project bad enough yet.
 
  • Like
Reactions: DarinC and JS8588
#236
koshkin said:
The statement that terminal ballistics are equal or better than the 308 is straight up lying.
Click to expand...

I'd like to see your source for these claims, otherwise it sure sounds like a false flag argument. We've seen charts posted showing higher velocity than the 308, but lower energy as any reasonably compentent shooter would expect. I've yet to see anything published about "terminal ballistics" compared to the 308 or anything else, so please post a source, otherwise let it go.
 
#239
5RWill said:
think the 103 in a 12.5” would nearing 2450?
Click to expand...

I could believe 2400 with a warm load, maybe a bit faster with a fast barrel. I haven't seen testing results that say as much yet, though.

I'm not condoning it but I suspect you'll see velocities that exceed the factory ammo because people who reload mostly rely on visual cues on the brass/primer which won't show up until much higher chamber pressures than what's recommended for the bolt thrust with a Grendel bolt.
 
  • Like
Reactions: Eccentric and 5RWill
#241
Yondering said:
It's the same case with a smaller bore - of course it will sacrifice more velocity when going to shorter barrels. That's how this stuff works; larger bores and heavier bullets are more efficient in short barrels.
Click to expand...

Obviously, that's why I wrote that.... What's your point?
 
#242
Ledzep said:
I could believe 2400 with a warm load, maybe a bit faster with a fast barrel. I haven't seen testing results that say as much yet, though.

I'm not condoning it but I suspect you'll see velocities that exceed the factory ammo because people who reload mostly rely on visual cues on the brass/primer which won't show up until much higher chamber pressures than what's recommended for the bolt thrust with a Grendel bolt.
Click to expand...

Which is also why you see some really balls out loads being tossed around for the 6.5 Grendel, when factory ammo and book loads are usually a bit more sedate velocity wise.
 
#243
Ledzep said:
I could believe 2400 with a warm load, maybe a bit faster with a fast barrel. I haven't seen testing results that say as much yet, though.

I'm not condoning it but I suspect you'll see velocities that exceed the factory ammo because people who reload mostly rely on visual cues on the brass/primer which won't show up until much higher chamber pressures than what's recommended for the bolt thrust with a Grendel bolt.
Click to expand...

I see that might be very tempting. I’m getting right at 2300 with a 123gr sst and 8208 out of my 6.5 Grendel. But it was crushing case mouths so i assumed it was over pressured. Haven’t reloaded much with the semis.
 
#244
koshkin said:
I have not yet seen an ammo introduction where the manufacturers were not either mistaken about velocity or lying about velocity or paying some gunwriter to lie about velocity. And that's before we get to them saying nonsense about accuracy, barrel life, terminal ballistics, etc. I think I already saw somewhere that 6mm ARC offers better external ballistics and terminal ballistics than 308.

Best examples are 6.8SPC and 224V, but there are plenty more.

Once factory ammo is reasonable available and well explored, we'll see. I am not buying anything off of media blitzes with hand picked and hand made ammo. It is not uncommon for early hand picked loads to be running at higher pressure for better PR.

Now, given what we know about all the 6mm Grendel wildcats out there, I am much more hopeful about this cartridge than about most others I have seen introduced for a while, but I will still wait.

ILya
Click to expand...
+1 2700 out of a 18” seems very unlikely.
 
#245
My accuracy node with a 243win 20” 7 twist with 108’s and h4350 was only 2860.

it bang flopped everything it touched and absolutely was more in terms of terminal performance then what an 18” rifle length can do with 77gr tmk.

this is the cartridge i’ve been waiting for for years. Stoked to get a barrel and bolt and bang flop a truck full this fall.Gotta love credit card reloading.
 
  • Like
Reactions: deersniper, yellowfin and Gtscotty
#247
ajwcotton said:
I've chambered a couple bartlein's at 22 inches and they were right around 2700 with 108's. One of them was in the hornady press release pics and videos. They were getting the same with it as the ammo I had.
Click to expand...
I was under the impression that Hornady was saying 2850 from an ar the one in the video was shorter than 22
 
#248
Nimothy said:
+1 2700 out of a 18” seems very unlikely.
Click to expand...

Not outside the realm of possibility, but on the top end for sure. In the "by the inch" test I saw 18" was around 2600fps. I have a Cz527 that is in 6 ARC with an 18" barrel that is also right around 2600fps with 108's.

Some barrels are faster than others. Like I said, 100fps isn't outright bogus but I wouldn't expect it to happen every time.

ETA: My rifle is a custom build, not saying CZ will be making factory 6 ARC's. They should, but I don't know if they will or not.
 
  • Like
Reactions: Srlurk2
#249
koshkin said:
I have not yet seen an ammo introduction where the manufacturers were not either mistaken about velocity or lying about velocity or paying some gunwriter to lie about velocity. And that's before we get to them saying nonsense about accuracy, barrel life, terminal ballistics, etc. I think I already saw somewhere that 6mm ARC offers better external ballistics and terminal ballistics than 308.

Best examples are 6.8SPC and 224V, but there are plenty more.
Click to expand...

Dude, preach it! 25-45 Sharps and 22 Nosler and 22 Grendel fooled me. I'm done chasing AR15 cartridge snake oil, especially with handloads. 224V Hornady ammo has been true on velocity in my experience, to be fair. I'll keep my Valkyrie barrel, but I'm not in love with it.

I'm a solid Hornady fan these days, and have been thinking for years that a factory offered cartridge like 6mm AR (sorry Robert Whitley) is the ticket, so a new barrel in 6mm ARC is probably in my future, probably 22".
 
  • Like
Reactions: deersniper
You must log in or register to reply here.

Similar threads

V
Advice on Cartridge and Rifle (and a lot of other stuff) for High Accuracy Bolt Action Rifle
Replies
21
Views
501
Dead Eye Dick
Dead Eye Dick
glock24
Long OAL in 6.5 Grendel Bolt Action
Replies
1
Views
555
DacianMH
DacianMH
E
New PRS rifle for old benchrest shooter
Replies
57
Views
4K
Kocher
Kocher
M
M855A1 Accuracy and Velocity
Replies
57
Views
13K
JKGTR
JKGTR
M
Black Hills 223 Remington 75 Grain Match HP Ammunition Accuracy Evaluation
Replies
11
Views
3K
Im2bent
Im2bent
Top Bottom
Back
Home
Forums
Merch
Alerts