6mm MAX vs. 6mm ARC: What's the difference?

We are joined again by 2A Fulfillment / SOLGW pro shooter Mike Russo for a kitchen table discussion on the 6mm MAX. Mike has been testing 6mm MAX ahead of the cartridge's production release and shot the rifle in the Quantified Performance gas gun championship finale at Arena Training Facility in GA, taking the win and the championship title in the General Purpose division.
We discuss the merits of 6mm MAX compared to it's small frame cartridge counterparts, 5.56mm and 6mm ARC. We also compare the components and ballistics of the cartridges and why 6mm MAX might win out.

[@gforce0311]

I always thought the simplest and sure improvement for the M4 was up sizing to 6mm

[@Mike-xi4zt]

It's my understanding the case is a rebated rim based off of the 350 legend neck down to 6mm. Not the 223/5.56 case necked up to 6mm. That's been done decades ago.

[@CptFUNK1]

Having broken a 6.5 Grendel extractor and only being able to use 10 round magazines reliably, I welcome this round and look forward to using it.

[@BuckF0eJiden]

6.5 Grendel will feed reliably out of the Duramag 7.62x39 30 rounders. C-Products feeds them, too. If you're breaking extractors, try increasing your buffer weight, and/or adjusting your gas, if an adjustable gas block/gas key is an option for you.

[@DB.KOOPER]

@@BuckF0eJiden ^THIS^ been shooting the 6.5 Grendel since it was introduced and I've hunted with it for years here in the PNW. I've had 25rnd C-products mags run perfectly for me and never broken a bolt/lug/extractor. I've got 2 rifles, one with a 16" Faxon Match bolt/barrel and a 20" BA Hanson barrel with a JP bolt, both run flawlessly.

[@BuckF0eJiden]

@DB.KOOPER most people don't shoot enough to see broken extractors or bolt lugs in 6.5 Grendel ARs. Even if you're running a massively over-gassed system... you're looking at around 1k rounds before issues pop up. Most people won't get close to that in their rifles. I have around 3k through a 6.5 Grendel with properly adjusted gas, and I'm keeping a spare bolt, cam lug, and firing pin in the pistol grip of that one, I'm expecting it to go just and day now. Keeping extra bolts and parts on hand is a pain, but it's not expensive or hard to replace. 6.5 Grendel is absolutely usable in both hunting and duty applications because of this. Just never let your bolts go over 1500 rounds, and you'll never have an issue.

[@phillycheesetake]

I know it's an AR cartridge, but I'm really excited for bolt guns to come chambered in this. With the taller shoulder and mag length limit, the chambering will be tight enough to set lighter bullets at the same jump as the heavier ones. The 80 grainers at bolt-gun pressures will be screaming out of a ~20" barrel, deer beware.

[@Paintballguru92]

Bolt gun master race crew checking in - totally agree.

[@milesrost6674]

the ability with the more rugged bolt face to increase pressure SIGNIFICANLY result in loads capable of 3900 FPS at muzzle, laying down some serious destruction to the target!! Cheers!

[@omarstephenson7000]

Wait until some AR-uppered lever guns start getting released into the market. Can I get a "Yeeee-Hawww!" ?

[@DB.KOOPER]

Been running 6.5 grendel since it's inception. Hunted with it and put thousands of rounds through 2 different rifles one with a Faxon BCG one with a JP and I have a cheap PSA BCG I keep in my rifle bag just in case... Never needed the backup and I;ve never had to use the curved mags. I run C-products 25 rounders and have -never_ had a feed issue or any type of stoppage. The 6MAX looks like a cool round and a great improvement over the 5.56 but the 6.5 Grendel and 6ARC don't have nearly the troubles in real world usage that all the theoretical discussions always bring up. 123gr SST from my 16" 6.5 Grendel "mountain rifle" sure does a number on the White Tail and Mule Deer I hunt up here in Idaho. I've even taken a cow elk with the round.

[@maguslascivious4980]

The real question is will 6mm max be supported by the manufactures. This also, in a way, supports my desire to have a slimmer case for the ar10 platform. Get more rounds in the magazine, run the longer bullets, have reasonable firepower.

[@steveelder5306]

it runs in a ar15

[@maguslascivious4980]

@@steveelder5306 I know... I was saying, if you could get a slimmer case in a ar10 length mag, you could have a big brother to this and fit more than 20-25 rounds. IIRC you can trim 5.56 pmags on the inside to get 30 rounds of .350 legend to fit. It's a thought I've had for a while but I don't have the space or time to make it happen. So imagine one of the small platform ar10s (SFAR, DPMS G2, POF ETC) with an ar15 face bolt in the carrier, pushing a longer case with a smaller OD than ..308. .308 has a base diameter of .47, .223 has a base diameter of .376. Doesn't seem like a lot but it's enough to change magazine capacity. .350 legend (parent case of 6mm max IIRC) ahs a base diameter of.39. So lengthen that case for the OAL of an ar10 mag, stack more rounds, have fun wild catting lol. Same thing with a 6.8 spc case at .422 base diameter, increase the OAL, neck it down to 6mm or 6.5, hell bump it up to 7mm, and have fun! While you're at it, run an Ackley shoulder. As far as the 6mm max, It'd be great if the industry would support it. 6.5 grendel had some decent support before steel ammo got cut off. 6arc is made by 1, maybe 2 companies... Remember 6.8 spc... yea, me either.. lol.

[@steveelder5306]

I got what your'e saying @@maguslascivious4980

[@josephlong7420]

As a reloader, when Lee comes out with a factory set of dies I will get really interested in this. I have a bolt and a gas gun in 6 arc. If this becomes mainstream, the gas gun will get converted.

[@maguslascivious4980]

@@josephlong7420 It'd be nice if they'd fit in modded pmags the way 350 legends do...

[@billydanzz]

It's time to just redesign the AR's receiver set to be slightly larger....as LWRC has done with their 6.8 SPC platform. Then you can come up with any cartridge/magazine design that isn't restricted to the current OAL, will surpass 5.56 terminal ballistics, and still be much smaller than the AR-10.

[@dvazquez5652]

Like the AR12?

[@billydanzz]

@@dvazquez5652 No. Not the AR12. "Slightly larger" does not mean the next size up.

[@maddawgmr]

Someone is working on that for the ARC itself, built a purpose driven platform around the cartridge.... wait for it... correctly.

[@Loganthehunter11]

I don’t disagree, but guys like the idea of interchangeable parts. If you break a bolt with 6 max you can run to the nearest shop and get one, with a proprietary system you’re kinda dependent on availability.

[@amiltomx]

Great information! It deserves a better microphone.

[@allnet135]

Love the idea of this round I'm getting one as soon as possible

[@herknorth8691]

The Grendel-based mags leave heaps to be desired. Any step away from them is a positive thing, IMO.

[@joshb5719]

Not to mention they look super ugly. The straight mags look way better

[@whiskerbiscuit99]

I run several duramag stainless 10rd mags for my 6 arc builds, zero issues with any of them. But some other brand grendel mags i havent been so lucky with.

[@YERAFirearms]

How much does it cost to replace a Grandel Bolt? 60-70 bucks?

[@andym82376]

Who's going to be the making barrels for the 6mm Max?

[@fl_protection]

I believe I heard Sons of Liberty will be making them

[@SnapD24]

Asking the real questions... So far SoLGW is the only one planning on having rifles and barrels available.

[@benanderson7417]

Why didn’t you compare both using the same 103? Comparing the 108 to the 103 seems a bit misleading.

[@sunandshadow_llc]

This is all from a competitor perspective. We are comparing top options for competition. While they are both 6mm, I don’t see 103 6ARC in the same use case as 103 6MAX. 108s in 6ARC have higher BC and would be a better option for comps, while 108s are on the too heavy/long side of 6MAX. 103s would be the competition option for 6MAX. Comparing 103 to 103 isn’t the same use case. This is similar to comparing 5.56 loads for competition; we’d compare 77gr and 75gr without question, but if we compared 77gr to 55gr for longer range competition, we’d know that they are not in the same category, even though they are the same caliber.

[@stevenmartens6692]

Exactly 💯 %

[@stevenmartens6692]

​@sunandshadoif your talking BEST options their are better then the 108

[@chadperry4021]

What the 6 max lovers aren’t telling you is 2/3 of the bullet is buried in the case. Anything above 80 grains just devours room for powder

[@lucastonoli3256]

Yes, 5.56 does wear down bolts and eat up lugs after a while. In the range between 15k-20k rounds any bolt will give up or start to fail, even LMT or DD. It's an absurd amount of rounds, but it happens. With shittier brands, you might see it earlier. I hope this cartridge catches on, looks like the winning balance between power, size and performance.

[@maddawgmr]

I think we can all live with those numbers!

[@TheTGRproductions]

Still a lot more reasonable than what the Military is trying to do. They claim the new the M7 with the 6.8 x 51mm round can withstand 6,000+ rounds before needing a barrel swap. Although I don't remember if they stated if that was with the Hybrid Loads, or the training loads. Either way, 6mm MAX seems like a much better choice to equip standard infantry instead of giving them a full powered Rifle!

[@randallvann7390]

Anyone have links for dies? Load data? I read SOLGW should have barrels or at least in the works. Been itching for a 6 arc. But fumbling between bolt or gas. This simplifies things.

[@sunandshadow_llc]

The BCPB site has Lee dies and load data! bcprecisionballistics.com

[@Feign_Way]

I wonder if anybody has looked into the 7mm TCU cartridge. I love that round.

[@robertjackson1407]

Thank you 😊

[@chadillac95]

Are you able to shoot the same heavy bullets that the 6mm ARC is shooting without taking up powder capacity? And what's the difference between this and the 6x45?

[@sunandshadow_llc]

Check out our article on 6MAX that explains all your questions! www.sunnshadow.com/post/6mm-max-a-comparison-of-top-performing-small-frame-cartridges-and-ballistic-data

[@blazinggsx]

105 gn max. So the really popular bullets in 6mm are not compatible. Thats was a no go for me.

[@maddawgmr]

@@blazinggsx 107g max but it gives no ballistic incentive over the 103g (which IME are superior to the 105)

[@texas66]

So can I just ream out the chamber on my 6x45mm and fireform my 6x45mm ammo to the max chamber? Who has reloading dies for it?

[@HWG-wm8ld]

The 556 does what it needs too. It’s at .60 per round in bulk. This new magic round will be over $1 per round for FMJ. Gun geeks need something to talk about and it’s the 6max.

[@maddawgmr]

Best thing is you can use what you want! We're just here to share information.

[@coreymoyers5771]

The slower-burning powder requires a longer barrel, which is in the opposite direction of all the progress made over the last twenty years. To significantly increase performance, you need more powder. As people often wrongly believe, the higher pressure doesn't increase overall performance. Sig's higher-pressure round was developed so they could utilize shorter barrels with the faster-burning powder. This is confirmed when you watch the 6 Max video from a 10.5 barrel. The performance is there, but so is that massive flame out of the silencer. That's not going to work for the military.

[@WanderingBobAK]

May be good content, but sound quality is lacking. Look forward to future posts.

[@maddawgmr]

Thanks for watching though! Jon has new mics now ; )

[@tontosilver6578]

So, in terms of performance other than 5.56... which one is better? 6mm arc or 6mm max?

[@maddawgmr]

It's real hard to beat a 106g A-tip (ARC) but again the point here is reliability in MAX vs lack of in ARC with few exceptions.

[@TheTGRproductions]

6mm MAX, hands down

[@jameshwang4750]

Brass and die availability?

[@sunandshadow_llc]

Both are currently available on the BC Precision Ballistics site! bcprecisionballistics.orchidnow.com/products

[@bfdadventure]

I was/am a little excited about this cartridge, but there are some grave mistakes being made on it's launch that are going to doom it for the long haul. Not meeting launch dates, only 1 barrel supplier, and 22 ARC drop at the same time. I am not happy about the inflated velocities and billing this round to compete against the 6ARC. This 6MAX is a 77SMK 5.56 beater.

[@mattcomchoc2957]

i've been following it's development as well. can you provide some citations for the things you mentioned?

[@bfdadventure]

@@mattcomchoc2957 sure: Hornady released news of the 22ARC. Multiple manufacturers have already produced barrels. Sons of Liberty Gun Works is the only manufacturer of the 6max barrel. Phone conversation with Brian at BC Ballistics, cartridge designer confirmed. Brian of BC ballistics also claimed launch date November 1 2023. Extended to Dec 1 2023. Still hasn’t been released. I’ve been watching cartridges rise & fail to stick since 2002. Remember the WSM lines?

[@zzeegermantube]

What are the actual caliber dimensions of the 6mm MAX? 6 x ? mm. The ARC is 6×38mm.

[@maddawgmr]

.243 dia and 1.263 bullet length on the 103g eldx

[@TheTGRproductions]

6mm MAX is technically 6 x 43mm, since the 350 Legend (9 x 43mm) is it's parent case.

[@bubba7626]

looks like you would get more throat erosion with the 6mm MAX over the 6 ARC due to the shoulder geometry. But yea damn! I have alot invested in 6 ARC but am cosidering transitioning over now to the 6 MAXX due to the increase in realiability,

[@maddawgmr]

Both have little throat erosion. The pressures are tame vs max spec for pressure

[@JamesBond-ut5iv]

I'm interested. I've been hunting for a small frame AR cartrige that gets me to 1,000 yards. I feel like this might be the one.

[@whiskerbiscuit99]

Thats what the 6 arc, or valk, or 22 arc is..... can you run the heavier 100+ grain offerings in 6 max?

[@maddawgmr]

@@whiskerbiscuit99 103, 105, 107.

[@robertabbott8541]

I didnt see any difference in the trajectory or wind deflection in the chart that he showed. 2 different bullet weights. So the only reason is reliability of the gun. Thats a lot of inertia to overcome. Especially with the arc falling off interest wise. Compare 6mm max to 6mm Primal.

[@maddawgmr]

Compared to the ARC reliability is what shines but there is a lot behind that one word, and it's all awesome!

[@whiskerbiscuit99]

Arc falling off interest wise? Your joking right? Sure the initial push is over but there are plenty still building and buying 6 arc barrels, and now theres a ridiculous amount of guys waiting on 22 arc barrels. Any 22 arc ammo that hits shelves or sites gets scooped up by guys like myself waiting on barrels. Both arc catridges are here to stay, valk is whats fading hard, i know plenty of guys with takeoff valk barrels layin around (though i think many were early adopters when twist rates and federals crap ammo wasnt sorted yet).

[@baraboo-nb7hv]

no round takes 5.56 spot anytime soon what so ever. gonna hold on to 6arc for a long time. will be interesting to see what happens to 6max in future.

[@whiskerbiscuit99]

Yeah ill keep my 6 arcs, in the process of a couple 22 arcs also.

[@ArgolasBowmaster]

I'm not wholly convinced that 6mm MAX is going to be all that much of an ARC killer. ARC seems to be doing a good enough job of it by itself given the extreme limitation of ammo manufacturers producing the rounds(and rightly so since 5.56 and .300blk remain the most popular AR platform cartridges with .350legend competing with .450Socom and .458Bushmaster for the next slot, though I see more people looking for bolt guns in .350 than autoloaders in my area). Then there's a limited number of manufacturers producing rifles in meaningful numbers for 6ARC to have really been propelled into more mainstream success. Hornady was extremely tight-lipped about ARC when it first came out and imo that hamstrung the cartridge's potential. Plus the questions of reliability with ARC, while reasonable due to it's grendel origins, could be at least mostly ironed out with time since it is still a fairly new round esp when compared to .300blk or even 6.5grendel and 6.8spc/spc II. 6mm MAX seems to be trying to solve a problem that really wouldn't be there if the industry actually took the time to properly work out the teething issues with each of these "super cartridges". At this point it seems more like a junkie chasing a high that never really gives the same return on investment as that first hit(in this case being 6.5grendel and 6.8spc) where, it is true that these cartridges all solidly outperform the 5.56 ballistically at comparable ranges in exchange for certain concessions such as mag capacity, they hardly seem to offer any significant improvement over each other to be worth tooling up an entirely different setup in a mass production sense. One of the main reasons I see .300blk having the level of success it has seen is due to its versatility in its use, production and load options. A .300blk uses everything the same as a 5.56 except barrel more or less so fewer proprietary parts, it can load virtually all the same bullet weights as .308 and then some and this flexibility also makes it excellent for suppressor use which lends itself well to both home defense as well as small to medium game hunting at the avg ranges your everyday hunter may encounter(sub 300yds in most cases in the continental US where case restrictions don't persist). Long story short, there's so many factors that lead to a cartridge living or dying so to speak and until I can see for certain 6mm MAX will tick all those boxes or any other wonder round for that matter, I won't rush to change over all of my rifles any time soon.

[@hunttomuchwolfe]

6mm max is just a new version of a 6mm223 or 6x45 that has been around for years

[@maki3336]

You guys have been holding the hand of the 6 max and slamming the 6 arc. You guys should stop slamming and just go with the casing, which is the game changer. If you go down to 105 grain with the 6 arc, performance will be the same, if not better for the 6 arc. The cost and availability of the 6 max ammo will make or break it. We don't need anymore $1.70 round ammo.

[@maddawgmr]

Well when you can't run an arc reliably for more than 1000 rounds at most, for 10k rounds straight, it's just my experience. And many, many more folks experience. No slamming, it's all fact.

[@koengCO]

🔥🔥👍👍

[@ColinFahey]

20 round GI mags usable? new follower?

[@sunandshadow_llc]

No, you'll need to use .350 Legend mags to accommodate the slightly longer load length of 6MAX and the feed lip geometry.

[@shootingwithsheps]

So is this just a dug up 6x45 that we shot back in the 90s and y’all wanna call it a max ? It was a benchrest winner in the early 70s also. I’d love to hear how this max differs from a necked out 223 to 6mm case.

[@CptFUNK1]

Rebated case head with a straight wall diameter the same as 350 legend. It has superior water capacity to a simple necked up 223.

[@shootingwithsheps]

Thank you for the informative response! I look forward to this project as I’m a big 6 arc fan

[@jjmckay6man1]

yep 35 gr of water in the 6max case.@@CptFUNK1

[@fl_protection]

This round is really catching my attention.

[@popinmo]

to fix the issue with polymer mags perhpas we could have custom loaded rounds that are shorter?

[@davidhernandez9985]

It's the first time touching down with Mike; permission to come aboard, excellent video of AR-cartridge expanding ammo. It produces more fire-power lasers from one's quad-laser. Happy Merry Xmas🎅🏻 to sir, you & your family!

[@katana258]

great if i could hear you

[@maddawgmr]

yeah... we know thanks for watching though!

[@guardianminifarm8005]

Interesting. Well done. Thank you.

[@tompanek7511]

LMAO He says he knows little about ballistics. He talked about feeding issues. I have two 6 ARC rifles - Both run like typewriters. NO feed issues and NO bolt issues. Too bad the M16 did not start out with a 6 mm bullet. 6 max is late to the party.

[@joelbuck5033]

What are considerations on reloading? What are expected case life’s?

[@clintivy623]

I have been told by sources that should know it's been very good if loaded to recommended pressures

[@maddawgmr]

The brass as of late was stopped in testing after 7 reloads.

[@3231bsln]

Is this the standardized 6-223 wildcat?

[@josephlong7420]

This is based on the 350 legend case. The 350 is a slightly larger diameter than the 223/556 case. I had to double check in my reloading manual on the case sizes.

[@kevinfox1780]

I'll never understand why this hasn't been done before. Expanding the neck of the 5.56 round makes so much sense.

[@wulf0101]

The 5.56X45 necked up is the 6x45, there is also the 6x47Rem. This guy is supposed to be built from the 350L giving it a little more capacity than a straight x45 derivative.

[@tompanek7511]

I agree! But I will say both my 6 ARC guns have never had any feeding issues. Both run like old fashion type writers.

[@steveelder5306]

its been done before. everything has.

[@methylmania]

Same here. No problems using cheap 25 round AR stoner mags. Not sure who makes them but they're GTG. I use an enhanced Aero lower on mine@@tompanek7511

[@Chumlee1000]

@@wulf0101 And a 223 duramag will let you load the 6x45 out COL 2.305. If you reload the 6x45 is simple 1 step sizing. Range pickup brass is cheap or save your 223 brass. The 6x45 round is what the military should of done instead of the 5.56. There is the 25-45 Sharps also, along with 277 wolverine, 6mm mongoose, 6.5 PCC (Patriot Combat Cartridge) or go down in caliber 20 Tactical ( I have) or 20 Practical- either of which keep up close to the 204 ruger. If there is something the 223/5.56 can be made into its more then likely been done already.

[@jazon9]

How will be comper 6mm MAX vs 6mm WOA?

[@jbcaptain11]

Clean your chambers with amazon wood qtips or run a piston system on the ARC. Cost of ammo is really the factor that keeps 556 and 762 R the best AR calibers

[@maddawgmr]

Chambers have had little or nothing to do with issues I've had with the ARC.

[@Chris-ob8ok]

This cartridge is DOA.

[@spenser5762]

So you are saying if I shoot 6mmMAX I stand a chance of being as handsome as MADDAWG?

[@wsaunders64]

😃

[@maddawgmr]

xoxo

[@stevenmartens6692]

why didn't yall compare 103 to 103 ????????????? Apple's to Apple's 🍎

[@sunandshadow_llc]

If you consider the cartridge/case designs, they are not actually apples to apples. 103 is considered heavy for 6MAX while 103 is medium/heavy weight for 6ARC. However, you can find info on 103 vs 103 in this article we did, and you'll see there's not much difference ballistically between the two: www.sunnshadow.com/post/6mm-max-a-comparison-of-top-performing-small-frame-cartridges-and-ballistic-data

[@Wilt11-14]

Give us a 6.5 max! Fix the grendel too!

[@maddawgmr]

I'd look at what BlackArc Munitions is doing with 6.5 and NAS3

[@or6060]

having SOME taper like the 5.56 is important for easy separation of the case from the chamber wall. also using a 5.56 case and 5.56 OAL would let you use 5.56 mags, which is why .300 blackout has been able to transition from a niche cartridge to something established within the industry. it's nice to use the same bolt as a 5.56, but i don't think it will be enough. no proprietary mag cartridge has ever succeeded for the AR. the two victories have been .300 blackout and 6.5 creedmoor for the AR10 which, like .300 blackout, uses standard mags.

[@kirkmartin2223]

6.5grendel caught on and spawned the 6arc and now 22arc which are both new but very popular. 6.8spc and 224valk are still popular in some hunting circles. Then you have the guys shooting "AR47" type rifles in 7.62x39. Also the 204ruger is around and uses everything 5.56 except the barrel. 350legend was the only ammo on the shelf during the plandemic.

[@or6060]

@@kirkmartin2223 none of those cartridges save 7.62x39 are within the same zipcode of popularity as .300 blackout and 6.5 creedmoor, and they're even farther away from 5.56. .22 arc just came out, how can you say it's popular? it's easily the least used out of all those cartridges for that very reason. 7.62x39 is not some meme round invented to chase industry trends, you can't compare it at all. none of these cartridges were on the shelves. each new 6mm whatever round for the AR further thins the consumer base, which is why all of these rounds are incapable of any real mainstream appeal.

[@kirkmartin2223]

@@or6060 6.5cm is an AR10 size cartridge so let's leave it out of the conversation. All the cartridges I mentioned are popular with people who hunt with an ar15.

[@or6060]

@@kirkmartin2223 ar15 vs ar10 doesn't matter. the point is that it was a new cartridge for an incredibly popular autoloader that found mainstream success. nothing else has been able to compete with .308 for market presence. and none of those hyper niche 6mm rounds will ever come close to .300 blackout's success. and by the way, .300 blackout is a better round for hunting than any of those.

[@curtdeichman2560]

I will keep my arc , 6 max doesn’t work with heavier bullets . It will never take off

[@tedarcher9120]

Almost nobody needs bullets heavier than 105. Max will be a beast as it gives ARC performance with regular bolt and mag combo

[@TheTGRproductions]

6mm MAX will eventually take off because it only requires a barrel swap, as it uses the same 378 Bolt-Face as 5.56. Which saves you time and money. It also is superior as an AR cartridge, and is more likely between the two to see actual Military adoption. Plus it has a standard 30 round capacity, 6mm ARC is 25 rounds with the same magazine size.

[@camstocky2019]

Is it just me or is it infuriating the cases they are referring to are just out of shot most of the video... seems simple

[@blazinggsx]

6 arc can shoot all weights 6max cant. If you showed apples to apples fps comparison both with 103gn eldx instead of the 108eldm in the arc the arc prob would be faster. Im at 3700 rounds of 6 arc w a rca bolt w no prob. Never heard of any from anyone else. I have on 5.56 caused by an over torqued barrel. I suspect if anyone does break one it would be a secondary issue. If all you wanted to shoot was the light bullet why go 6mm. But hey push that new hotness

[@maddawgmr]

@sunnshadow put some content out on this.

[@TheSkylar25]

I always thought a necked down 6.8 spc case to 6mm would have been better than the 6arc for a lot of the same reasons.

[@michaelpicklo7888]

There is a few wildcats like that. I have one called Tac6. Necked and shightly shortened. Can outrun an ARC all day

[@oif3vetk9]

I'd like to see tests done with a 20"-24" barrel. Those certainly are good velocities for a 16" barrel but my preference is different than most I guess. I really like the fact it uses a 5.56 bolt. I've been lucky (If you want to call it that) and have broken only one extractor with ARC (And that was factory ammo) BUT that was the day before a match and I was at the range. (125 miles from home) I'm going to give this cartridge more time before deciding if I'm going to jump onboard with it. 6 ARC has been good to me and I have to admit, I'm also curious about 22 ARC. Wish I lived closer to where the Quantified Performance matches are held. All we have is PRS.

[@sunandshadow_llc]

We have test data from BCPB on a barrel length vs velocity chart in an article on 6MAX here: www.sunnshadow.com/post/6mm-max-a-comparison-of-top-performing-small-frame-cartridges-and-ballistic-data

[@sethperry1323]

I was looking at velocity chart for the 6max out of a 16" barrel its nipping at the heels of 243 win.... if that is actually true this is a predator hunters dream... even a 12.5" barrel with a silencer an thermal you have a lightweight package that is close in balistics to a big old heavy ar10... I was looking at a 243 but this is no brainer if your looking for a semi auto with a shorter barrel...

[@mattcomchoc2957]

243 is really a very inefficient cartridge. i hate that it's still so popular with so many other decent modern options out there.

[@jjmckay6man1]

.243 can hit over 4kfps with 55gr noslers the 6max is about 3500. .243 with 70gr sierra hpbt @ over 3650fps 6max 3300. 6max seems to get a bit closer with the heavier bullets. 24" barrel #s. 6maxs numbers still great out of a AR15 platform.

[@sethperry1323]

@@jjmckay6man1 i was looking more at the shorter barrels... 16" an down... im trying to think off the top of my head but a 16" 243 58 grain is running 3600fps maybe (factoryload).. there saying the 16" 6 max is pushing them out at 3390!

[@jjmckay6man1]

yeah .243 is not very efficient at all out of short barrels plus the noise and concussion would be insane lol.. yeah the 6max looks very promising to me as long as you aren't trying to use the heaviest projectiles. yeah the 55gr nosler shows 3500 out of a 20" on their load data on their site.@@sethperry1323 I have been loading my own for 25 years so I make all my own ammo. I don't mess with factory underloaded ammo. the winchester loaded 243 55 gr ballistic silvetips listed 4025fps when i used to buy factory ammo. so i would think you could get 3800 to 3750 with a 16" 243win. I wouldn't want that fireball and noise though a 22" barrel is loud enough with a 243win lol. I have both a 22" bolt gun and a 22" AR10 upper in 243win. The 6Max is very intriguing for AR 15 platform.

[@josephlong7420]

I had to grab my reloading manual to look at 243 velocity, your right. Your burning less powder and it's in a small frame ar.

[@tacticalwarrior5178]

6 MAX vs 6.8 SPC is going to be interesting. Since the Army is moving to 6.8 would they consider this new cartridge instead or is it too late?

[@lorcan2316]

They are moving to 6.8x51 not 6.8spc. And yeah it’s too late for a change of that size given sig sauer already won the next 20 year contract

[@jasonnyhof5972]

I have a LWRCI in 6.8 SPC and love it. I don't know what this cartridge will offer that 6.8 already doesn't for the average shooter.

[@tjkiller99000]

Terrible audio, im out