6mm ARC Round, Too Little Too Late?

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Opinion

Hornady 6mm ARC Ammunition, IMG Hornady Inc
Hornady 6mm ARC Ammunition, IMG @Hornady

Ft Collins, CO –-(Ammoland.com)- 6mm ARC (Advanced Rifle Cartridge) Hornady recently introduced its new, stubby 6mm Advanced Rifle Cartridge (ARC).

It’s basically the 6.5 Grendel, necked-down to 6mm (243cal), and will shoot a 105grain 243cal/6mm bullet.

The 6mm ARC is designed to run in existing in M4 rifle platforms.

I don’t know the velocity, but I suspect something under 3k. Barrel-length is an issue. An eighteen-inch barrel, maybe even a twenty-inch barrel, will likely be necessary to achieve reasonable ballistic efficiency.

Here we go again!

The 6.5 Grendel case (and this is a new case) doesn’t leave much meat around the cartridge head on the existing M4 bolt. One issue with the 6.5Grendel (in heavy use in the M4 platform) has been chronic bolt breakage. Maybe there is some new metallurgy, similar to what POF uses on their Revolution Rifle (7.62×51), but otherwise, I see bolt-life issues with this new round.

This new cartridge represents a ballistic performance improvement (improved range and penetration). No doubt. So does the 6.8SPC, which has been around and endlessly tested since 2004.

Despite all our conversation on this subject, I suspect DOD will be continually fielding M4s in 5.56×45 for at least another 10 years.

There are those who are naively seeking a single cartridge that will run in short M4s, but also render adequate performance in “designated marksman” rifles, sniper rifles, GPMGs, and also be available in both supersonic and subsonic versions.

Can we “have it all” in the same cartridge? It isn’t physically possible.

To convert existing M4s to 6.8SPC, or this new round for that matter will require a new bolt carrier group, new barrels, new magazines, maybe new springs and buffers. Even then, there will be inescapable start-up issues that cannot possibly be foreseen. There always are.

And, brass cartridge cases may be replaced with plastic! What could possibly go wrong?

The point is that this tardy update to the M4 rifle, even if it were implemented right now, is already thirty years late.

We desperately need a 300m auto-loading infantry rifle that shoots through-and-through things, and we haven’t had one since 1964. And at the rate we’re going, it will be yet another ten years before we get one.

/John


Defense Training International, Inc

About John Farnam & Defense Training International, Inc
As a defensive weapons and tactics instructor John Farnam will urge you, based on your own beliefs, to make up your mind in advance as to what you would do when faced with an imminent lethal threat. You should, of course, also decide what preparations you should make in advance if any. Defense Training International wants to make sure that their students fully understand the physical, legal, psychological, and societal consequences of their actions or in-actions.

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Jim
Jim
1 month ago

I’m all in with the 6mm ARC. The weapon weight along with ammo is a significant issue for grunts and scouts. As a combat vet with 5.56 experience, the military has needed a “better cartridge “ since the 1970s. The 6mm ARC will need wide spread use to prove its potential as an effective long range round (500 meters). However, most of us have experience with the AR-15/M-16/M-4 platform and the .243 Winchester round. With heavier bullets, it brings a whole, new perspective for troops. A piece of this is better marksmanship training. Otherwise a better long range round accomplishes… Read more »

Steelbustr
Steelbustr
3 months ago

I think it will be fine for MOST shooters but wont stand up to military use in the M-4. The ballistics are on par with the venerable 6BR. Remington needed to step up on the enhanced barrel extension and bolt they had for the 30 Rem fiasco. Maybe someone in the industry can revisit that.

Buck
Buck
3 months ago

What?? No “magic bullet” to be found? That can do ALL things?!??

SGT_Wombat
SGT_Wombat
3 months ago
Reply to  Buck

They had one in Dallas in ’63 didn’t they?

Will
Will
3 months ago
Reply to  SGT_Wombat

22 NOV.’63! A really shitty day for TEXAS!

Jason
Jason
3 months ago

I see you are a “the glass is half full” kinda guy. LOL

Xaun Loc
Xaun Loc
3 months ago

As an old-timer I appreciate all the advances in interior, exterior, and terminal ballistics that we are seeing, but I really wish that the industry would settle for just one or two new Wonder Rounds each week.

Despite all the hype, by the time we see any honest independent information about this round, someone else will have released yet another magic silver bullet that claims to punch one-hole groups at absurd distances while also being ideal for every other possible use of any rifle.

RoyD
RoyD
3 months ago
Reply to  Xaun Loc

Life is all about choices. The trick is to make as few bad ones as possible.

Bobtail
Bobtail
3 months ago

Sounds like a job for a magazine fed Garand.

Big Daddy
Big Daddy
3 months ago

So they had .223 V and I went out and bought a barrel etc etc now 6mm I think I ll just sit tight.

Old Vet
Old Vet
3 months ago

Don’t think you are giving the pro’s at Hornady a fair shake here. Let’s see how it performs in the real world and then do another write-up.

Matt in Oklahoma
Matt in Oklahoma
3 months ago

I doubt it will do what the military wants and I doubt any powder fueled cartridge will do what it wants especially your desired 30s. They want body armor punched at hundreds of yards with little recoil and a small lightweight compact package. It’s time to look beyond powders and into the next phase.

Erik
Erik
3 months ago

Typo in the title: you mean “too little, too late”.