What AR15 cartridge is a worthwhile step up from 5.56?

[WindstormSCR]

Another barrel, bolt and mag has you up and running with a 6.8 or 6.5, what is a properly made 6arc?

Properly made = a set of parts designed with it in mind, and/or properly tuned.

It was a statement that was intended to imply that any unreliability in the 6 Arc is the vast majority of the time the result of poorly executed or poorly tuned builds, same as it is for grendel or 6.8

 

[346ci]

Properly made = a set of parts designed with it in mind, and/or properly tuned.

It was a statement that was intended to imply that any unreliability in the 6 Arc is the vast majority of the time the result of poorly executed or poorly tuned builds, same as it is for grendel or 6.8

Figured so, wanted to make sure we were on the same page.

 

[ironpony52]

SIGs new 277 Fury....now I have to buy another CROSS.................

 

[81STFACP]

SIGs new 277 Fury....now I have to buy another CROSS.................

Go for it, tell us all about it.

 

[ClangClang]

I'm enjoying all the minutiae of diving down caliber rabbit holes. I personally went with an 18" Proof CF 6mm ARC upper for my alternate caliber just for fun.

As for OP's question, for an AR15 for implausible future SHTF situations where he'll be bugging in with his parents, the OBVIOUS choice is any bog standard 16" chambered in .223 Wylde. It's silly to choose anything else for dozens of reasons, all of which have been articulated over and over in this thread.

 

[Gtscotty]

Not for nothing, but every bit of publicly available load date says your factory 108ELDM ammo is over 52kPSI. Hornady doesn't use LVR in their factory ammo but it appears to be the closest analog I can find.

If you say so boss, sounds like speculation to me without knowing what non-canister powder Hornady used, or having any pressure data or even reports of pressure signs on my brass. You'll have take that up with Hornady if you have concerns about their factory loads complying with the SAAMI spec they established though.

I will say, a lot of my few hundred pieces of brass came from factory 108 ammo and have several loads on them. In my experience loading Grendel and ARC spicy in the past, primer pockets tend to go pretty quick when you're pushing them.

 

[Cascade Hemi]

If you say so boss, sounds like speculation to me without knowing what non-canister powder Hornady used, or having any pressure data or even reports of pressure signs on my brass. You'll have take that up with Hornady if you have concerns about their factory loads complying with the SAAMI spec they established though.

I will say, a lot of my few hundred pieces of brass came from factory 108 ammo and have several loads on them. In my experience loading Grendel and ARC spicy in the past, primer pockets tend to go pretty quick when you're pushing them.

It sounds like OP would be best served with some flavor of 5.56.

Your posts remind me of when Grendel came on the scene; the fresh converts out proselytizing their new lord and savior. They gotta confront anyone with even the slightest contradictory opinion.

It took all of 30 seconds on Google to find reports of high pressure with that ammo. I don't need to take anything up with Hornady, this sure isn't the first time they've put out some spicy initial loads (Hello 6.5CM intro!). You're free to keep on keeping on and if you don't like my opinion don't quote my posts. Have a great day.

 

[Gtscotty]

I'm not proselytizing, but I do resent speculation masquerading as knowledge. I posted some actual information, data and experience with both. You started off with a nonsense comparison of two Grendel and ARC loads (are they even your loads?) that you later claimed were both lower end loads. You then followed up with vague speculation and "whatabouts", without actually posting a single bit of data or real information.

I'm all for seeing your actual load data and chrono data, but it's been scarce. If you're not interested in adding real information to the thread, why keep replying with low-content posts, just have to have the last word?

 

[Biggy]

6mm Max using the right bullets for the application in an AR15 sized platform.

 

[Jackal434]

What other cartridges that fit in an AR15 provide enough of an increase in performance (increased range, dealing with wind drift better, terminal performance, etc.) over 5.56 that make them a worthy upgrade from 5.56? I know there are the duds like the .224 Valk and .22 Nosler and there are also newcomers like the 6 and 22 ARC as well as the 6.5 Grendel that has been quietly chugging along; but do any of them bring enough of an increase in performance to the table to be worth owning? Or is it just the case that if you want a meaningful performance upgrade step up to an AR10 in .308/6.5?

Thanks for reading and looking forward to your responses.

P.S. this question may have been triggered by reading about what you all are doing with your 6ARC and 6.5G rifles and having a spare lower just lying around...

I have most calibers in my AR-15s. My three favorite are 6.5 Grendel, 6ARC, and 6.8 SPC, although 50 Beowulf, 458 SOCOM, and 450 Bushmaster are fantastic hardhitting rounds very limited in range. If you hunt with your ARs then for a long while it was very worth stepping up to these calibers. However, now that there are viable lightweight AR-10s in the Sub 7 lb and even Sub 6 lb territory it really limits the advantages of the magnum caliber AR-15s, although you can get them down to 5 lbs if you are willing to spend serious money on lightweight parts made with aluminum alloys, titanium, and carbon.