Is this just the commercialized version of 6mm AR? 6mm AR is the best 6mm round out of an AR-package that I've seen.

I don't think there is enough of a change from the Grendel for it to become widely popular, especially with the limited data that's been published.

24" test barrel doesn't help anybody.

LOL he ripped of the 6.5mm PPC.

Where's the wolf ammo?

Is it designed for longer barrels? I’m not nearly as buff as that Secret Service guy to walk around with a 24 inch rifle and suppressor.

AMU definitely didn't adopt it.  Quite the opposite really.

5th Group had at least one Commander who authorized studies and testing to be done with the proposed cartridge, not much beyond that.

JSOC acquired a large sample of 6.8 SPC carbines, ammunition, and magazines and did their own in-house high volume testing without some promoter trying to influence the tests, and wanted nothing to do with it after they were blowing up guns repeatedly.  No responsible entity really had control and ownership over 6.8 at the time, so all kinds of deviations from any of the initial 3 chambers, bore specs, and cartridge loadings were happening and colliding with each other.

Promoters of the 6.8 had to be escorted off of Bragg at least once by uniformed MPs at the request of units who were tired of being approached without solicitation.

There were several of the early 6.8 proponents who then traveled to the UK Ministry of Defense small arms people (without any official business orders or status) and told them, "This is the new 6.8x43 NATO cartridge developed by SOCOM, and that you had better get on board or get left behind."  These MoD people, having had a continual relationship with the US for generations prior to this, wondered what was going on because they never had these types of interactions before.  If something was actually sanctioned for R&D for NATO testing pre-standardization, they would have been notified through official channels and representatives and asked to participate.

They contacted the official DoD reps in the US who said, "What?"  It ended up resulting in threats of Courts Martial for anyone who was caught with 6.8 uppers, mags, or even as much as a piece of spent brass downrange.  They ticked off a lot of people across services, within multiple elements of SOF, and foreign partners, as well as the FBI ballistics lab.

If someone wanted to write a historical account of how not to promote a cartridge, the material available on the 6.8 "proponency" would make you shake your head from page-to-page asking if people could actually be that ridiculous.  People were fired over it and PNG'd from multiple locations and agencies within DoD and Federal LE for misconduct, misrepresentation, and attempts at fraud.

Shoulder location is shorter than the 6mm AR.

If you put the 2 next to each other, as well as compare the chamber development and extensive testing efforts from Alexander, you'd see how mistaken that is.

Guess it will depend on its success with the DoD buy. If it performs well and spreads some, you'll see 6.5G forgotten and the 6mm ARC be the mainstay.

People love to flock to military/government adopted rounds.

So a necked down Grendel.  

No advantage over a Grendel and the 6mm Grendel has been a thing for a few years.  


6mm at reduced velocity/energy compared to a .243Win, nope.

The 243 will remain popular but rifles came with too slow a twist to handle heavy bullets. The 6mm CM is very near the 243 in performance but with a faster twist it can handle both light and heavy bullets. This is a significant improvement and worthy of a new cartridge.

No.

If you set a specific muzzle velocity as one of the main performance metrics for a cartridge, you might be able to say "designed for longer barrels", but most bottle neck centerfire rifle cartridges have similar curves when looking at barrel length.

If you go to the extremes where you have low case volume and no real overbore on one end, then you can hit a place where more barrel length just doesn't give you a lot of velocity increase like with 300 Whisper.

But for bottleneck cases, they generally have very similar velocity curves relative to barrel length.

Less case volume, shorter barrels.

More case volume and you can increase the barrel length past 24" and still get performance gains, like with magnums and more overbore cartridges that have case capacity similar to .308 Win.

An 18" 6mm ARC will still push a 107gr high BC bullet in the .530 G1/.270 G7 range over 2600fps (2617fps).  That will be flatter and have less drift than a 24" Grendel shooting the best 123gr bullets (.527 G1/.263 G7)

That's supersonic to 1075yds, and still has 900ft-lbs at 425yds, 1 mil of wind drift at 500yds.

A 16" 6mm ARC Recce Carbine with spit 107gr at 2560fps

That's supersonic to 1025yds.

14.5": 2508fps Super to 1000yds

13": 2451fps Super to 975yds

Yeah, Grendel isn't going anywhere but up due to the amount of market support it has.

6mm Grendel variants like this are already proven as to performance.

The market isn't going to just up and forget 90+ factory loads and steel case availability, plus the benefits for hunting that a lot of people have gotten into Grendel for.

I see a lot of people who are new to firearms, or are just barely getting a peek into some things that have been happening over the past 2 decades pop in and think things are a certain way because they haven't heard of it before, so now their experiential reality somehow translates to reality in the market.  

Just to be able to get a new cartridge to break through into temporary recognition is a huge hurdle.

To get SAAMI approval is even bigger than that since they get approached with so many different wildcats by individuals and small shops throughout the year.  They have to turn people away as a rule if they don't have big manufacturer support.

Then to get one major ammo manufacturer to adopt your cartridge and put it into their schedule is another huge hurdle.

To get market traction with consumers based on the performance or marketing is even bigger.

To get other cartridge manufacturers to take notice and then start filling the rising demand is the next major hurdle.

Once you see all the major manufacturers getting on board year-after-year, then it has become mainstream.

Of the few cartridges that have been introduced over the last 2 decades, how many have steel case option?

That took 7 years of back-and-forth between Bill A. and Barnaul engineers working through an intermediary just to get the steel case specs dialed in correctly.

The availability of steel cased ammo for 6.5 Grendel is really, really compelling. And I do mean availability -- even now it's in stock in multiple places at reasonable prices.

Time will tell but the adoption of a cartridge by government entities appears to be a massive driving force.

6.5G has failed to do so and with 6mm ARC now gaining adoption before even hitting commercial side, it doesn't look good for it ever getting adopted.

Big Green, yes. But a component of JSOC? That's kinda different. LWRCi probably made more Six8 guns for their Saudi and Jordanian contracts than DoD is ever going to buy in 6ARC, but you don't see a ton of Six8 stuff out there in the commercial market. Magpul even made Six8 mags and Federal made 90gr Gold Dot contract ammo, IIRC.

90 grain, was the XM68GD load, does rather well from short barrel setups too. As for the Six8, there are two other companies now making receiver sets that use the mags.

There was a company that was going to make steel mags for it, to take advantage of a longer round but it's been quiet from them for a bit.

I do agree though, on the 6ARC having limited adoption.

So it's a 22 Grendel necked up to 6mm ?
Right?

Neat.  Another solution looking for a problem.

It neatly solves a DoD problem.

Whether it solves anyone else's problem is up for debate...

What dod problem does it solve

Apparently some Tier 1 dudes wanted a rifle/cartridge combo that drops bad guys at 800+ meters without the weight or size penalty of a .308-based rifle.

The cartridge is the 6ARC. The rifle is the Barrett Rec7 DI with an 18" Proof CF barrel.

A whole new generation of checking lot numbers, popped primers and "your rifle was dirty that's why it kaboomed," exciting!

sounds like 6.5g would have fit the bill then.

I assume they'd heard of 6.5G

Reported.

I was told one of the Seal Teams have been using it over the last year

I was one of those who fell to the allure of the .224 V and built a top tier rig, only to never fire it. I was about to sell the .224 components and rebuild as a 6.5G. I may have to wait and see if the ARC offers anything better. For my needs, I doubt it.

Why not just shoot the Valkyrie?

Bunch of luddites in here.

“This thing I know almost nothing about and have no experience with sucks.”

The internet told him it’s not cool anymore.

Apparently a bunch of early adopters whose guns see the range once a year got tired of spending more than 25 cpr to punch holes in paper, sold their uppers for pennies on the dollar and that means it’s a “dead cartridge”.

Good question. I guess after our 1000 yard range here closed I had trouble seeing how the 224 V offered much over a 5.56 with 77 grainer.  Maybe I'm wrong? At least with a 6.5G I would have a decent deer rig.

Funny, I don't ever remember talking to you.

Thanks for the feedback.  I haven't sold any of the 224V stuff off yet so may give it a go yet. I can shoot out to about 600 on our ranch without bulldozing a lane. I can always convert it later if it doesn't fill a need. I am going to keep my eye on the 6 ARC to see where it goes. Although the 6.5G seems to fill a real need and I like the idea of cheap steel case for practice.

This is why I havent bothered with anything other than 5.56. I have only one place I can consistently shoot at, and there isnt 100 yards to shoot, there isnt even enough to properly sight in the scope I have for my rifle. There was a gun club I was going to join, but then Covid happened, and they decided to shutdown for the time period (now im rethinking joining for a number of reasons).

For the most part 1000 yard accuracy is fantasy land bullshit.  I hand load and enjoy benchrest but outside of matches what's the point?     What's the point of cramming it into an AR?   Pure fantasy.  

There's practical and then there's on paper horseshit.  I'm filing this in the latter..

lol this wins. also DUPE.

https://www.ar15.com/forums/ar-15/New-6mm-AR-cartridge-6mm-ARC/121-749606/

Have you ever heard of the 6x35 PDW cartridge and PDW blasters made for TSWG by Knights Armament and Hornady?







I've said for years that a 6mm, .257, or 6.5 Grendel Designated Marksmen Carbine would be pretty ideal for adding significant high hit probability reach to dismounted units that are willing to actually train their personnel how to shoot.

If you think about all the work that has been done with 77gr Mk.262 and other SOF-specific ammo from guys who get shoot training, enemy combatants have realized that if you get this close to these guys, they can pop your melon, so naturally they learn quickly to maintain a certain stand-off range.

These types of rifles will be very limited in issue, similar to how many SCAR-H weapons might be carried out of the arms room approach SOF uses.

Within USASOC and NAVSOF, they've been configuring special carbines with free-floated accurate barrels of different lengths dating back to before the M4 and SPR for this role.



Stepping up to 7.62 NATO rifles made the job harder due to weapon size/weight, sight picture management, ammo weight and bulk, reduced ammo count on soldiers load, and problems clearing rooms.

It's a major problem we've had with small arms since the abandonment of the 6mm Lee Navy and .276 Pedersen, neither of which was given an opportunity to have staying power in the cartridge mix of dismounted US soldiers.

5.56 is great for a lot of basic infantry work within 200-300m.

It allowed units that used to be liabilities carrying 7.62 NATO rifles to have far more staying power and combat endurance just working out of the soldier's load they left the wire with.

You make contact once with 7.62 NATO rifles, and after one magazine, you're already thinking about how close you are to running black, how will you withdraw or resupply, consolidate and defend a hasty position, versus being offensive.

Equipped with 5.56 rifles enabled units to make multiple contacts and continue the attack, continue mission without need of resupply, and in worst case scenarios, have substantial ammunition to be able to defend until indirect fires or CAS can be called upon.

If I have 3 mutually-supporting maneuver elements and my lead element makes contact, after the contact is resolved, I can leap-frog my middle or trail element to lead with 100% UP on LACE (Liquid, Ammunition, Casualties=0, and Equipment).

If I need to redistribute ammo from a lead element that spent more than 25% of their ammo, our overall ammo state will not be that drastically affected once we've cross-loaded mags with the elements that didn't spend any ammo.

With 7.62 NATO, the numbers start off so small that even one lead element making contact significantly reduces our ability to fight if they burnt through 2 or more mags.

With 5.56 though, I don't have the reach and energy of 7.62 NATO, so we've always had a mix of 7.62 NATO weapons in the units, whether that was belt-fed or sniper systems.

But now my snipers are either carrying 2 weapons, or have a hard time fighting the close fight when we take down and occupy buildings or huts.

What if there was a way to have my cake and eat it too?

It would be great to have a light-recoiling cartridge that fits inside my existing M4 profile, but reaches out as well or better than 7.62 NATO.

Enter 6.5 Grendel and 6mm ARC.

6mm ARC has less recoil comparing 108gr to 123gr 6.5mm, flatter trajectory, less wind drift, and maybe marginally-less barrier defeat, but plenty to get the job done.

A lot of targets are fleeting or partially exposed targets anyway, so designated shooters need to be able to hit small at distance at UKD, which is easier with 6mm than 6.5mm for the same reasons it's easier with 6.5mm than 7.62 NATO.

The big difference is that designated hitters with 6mm ARC Recce-configured blasters can still clear rooms with about the same profile gun as an M4 or suppressor-equipped Mk.18.

Throw a modern LPVO on it and go to town.

So are you ditching 6.5g for 6mm arc?

Talk me through the applied physics of how that's going to happen with a 52,000psi SAAMI MAP.

That's way under 5.56 and 7.62 NATO MAP.

I think it was a joke and reference to the 6.8 fiasco and possible the knockoff Grendel problems as well.

Because the owner of the "grendel" name for cartridges is prone to getting into legal fights if someone so much as looks at something similar to his intellectual property.

If you ever get the chance to attend an 8-13 week course where you spend every day of 2-5 weeks doing nothing but precision and LR shoot work, then get to attend all the shoot work-up sniper sustainment training ranges on your pre-deployment schedule, shoot real-world for 150 out of 180 days on deployment, come back and go to whatever reputable civilian training facility courses, USMC high angle courses, and Team training there is, go to military sniper matches, then deploy again for more of the same, you start to get an idea of the caliber of shooters that wanted this capability versus the internet guy who rolls up to a local 1000yd range maybe once a year.

When you start to focus on a particular skill set like that and get more than 7000 good reps in regularly, dudes actually get pretty impressive with a rifle not only out to 1000yds, but well beyond that, even from an AR15 chassis with the right cartridge.  Certain elements within the SOF community do everything I described above.

If you know how to read the wind and apply LR fundamentals, making consistent hits at 1000m isn't particularly difficult, within certain wind conditions parameters.  As the wind gets faster and at full value orientation to your bullet path, the effective range pulls in noticeably, but 800m shots are still high hit probability with a good shooter in those more challenging conditions.

Not sure how someone would conclude that based on what I posted.

I have a bunch of Grendels ranging from 22" down to 12" with a 10.5" in the works.

I've always wanted a 6mm Grendel in addition to all my Grendels that will be an addition, not either/or.

Same with 5.56 NATO.  6.5 Grendel smokes 5.56 ballistically looking at energy, supersonic reach, etc.

I still have loads of 5.56 blasters, primarily for CQM work and loaners in my DM courses.

First I've heard of that.

People didn't like that Bill A. worked the front end to control the standards before SAAMI approval.

If there was a lawsuit filed against anyone, it slipped by me as a close follower of what has been happening since before 6.5 Grendel was introduced.

Way to jerk yourself off. Shocking as ever. Hes not talking about military deployments. Hes talking about 99% of shooters out there that can't hit shit past 500. Everything in life is not back in the good old days. Options are good thing and if this round works for people than more power to them. I would rather have a 77 grain normal ar15 or 6.5 grendel. If I need more than that I'll take a 6.5cm in a 16 inch gas gun.