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Ar15performace.com is working on a new cartridge for the AR-15 platform that promises to deliver game changing performance. If your thinking that sounds like a 6.8SPC think again. The 270AR will deliver at 200FPS more velocity from any barrel length compared to 6.8SPC. That 200FPS boost pretty much over comes the advantage that the 6.5 Grendel has in long range over the 6.8SPC. In other words this new cartridge will threaten the argument for getting either cartridge. Not that the 6.8SPC and 6.5 Grendel shops will pack up and go home this is a wildcat cartridge and will only be for home hand loaders.

Hand loaders should be able to load from 85gr to 140gr bullets making the cartridge applicable for varmints to medium sized game such a hogs, deer, antelope and caribou. I would expect some of the more adventurous to go after Elk with 140gr Berger VLD's. I don't have velocities for a 140 gr but even if we assume 2700FPS which is a low estimate we are in the big game range for Elk according to HITS. I know many traditional hunters think a .270 is to small for Elk but many Elk have been taken with a .270. Chuck Hawks tackles this subject here saying the 270 is adequate in his opinion but acknowledge's many hunters consider it an ideal caliber. The 270AR though is not an equivalent to a 270 bolt. As much as the 270AR has on the 6.8SPC the 270 bolt has on the 270AR. Still expect to hear Elk stories in the future from 270AR hunters.

The parent brass will be 6.5 Lapua or 6.5 Creedmore. The 6.5 Lapua is the preferred brass because its thinner and will hold more powder. The 6.5 Creedmore will maybe have a 50 FPS drop in performance from the Lapua due to less powder capacity according to the designers estimates. Hand loaders will take these parent brass cases and cut them down and reshape them using a modified 6.5 lapua reshaping die. No complicated fire forming required. This process will be very similar to what hand loaders are doing now with 5.56mm brass to make it 300 Blk brass.

From a 18in barrel the Hornady 120gr SST is going at 2860FPS and the 130g Berger VLD is getting around 2800FPS from a 20in barrel. The designer estimates that a 110gr bullet should be at or close to 3000FPS. Typically a 6.5mm Grendel max powder capacity is around 29gr compared to around 39gr of powder for the 270AR. This added push out the barrel makes up for the higher BC that the 6.5mm enjoys giving the 270AR much lower drops over long distance shooting. I put together a chart to compare the Grendel to the 270AR shooting 130gr bullets. I couldn't find numbers of a 6.8SPC for the 130gr to do a comparison for this gr size. Be mindful of the barrel length in this comparison because the Grendel has a 4 in barrel length advantage in this data. Read more at the the parent thread over at the 6.8SPC forum. ar15performance.com will be selling the barrels and bolt combos for 400 bucks.


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Last edited by SanCalPigHunter; 07/14/13.
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Sooooo, like a 270 Redding?


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Chuck Hawks and "H.I.T.S" graphs..

[bleep] awesome.


Originally Posted by captain seafire
I replace valve cover gaskets every 50K, if they don't need them sooner...
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Simply revolutionary.

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I'm sure Field and Stream is going to do an article about it. I can't wait..


Originally Posted by captain seafire
I replace valve cover gaskets every 50K, if they don't need them sooner...
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Too bad they didn't make it a 6.5 or 7mm, on the same case.


I guess 270 is something the average beer belly understands.

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Originally Posted by exbiologist
Sooooo, like a 270 Redding?



No, the Redding is on a .308 case, right? This is based on the .250 AI or .300 Savage case, which would make it equivalent to the old .270 Titus.


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270 Redding isn't going to fit in a AR-15 and 270AR is based on a 6.5 Creedmore and 6.5 Lapua which both fit a 308 bolt face. The 270AR has the same case capacity as the Remington 30AR.

Last edited by SanCalPigHunter; 07/14/13.
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Almost as good as the 6.5 Grendel or the 264 Baer; almost, but not quite.

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If both tables were from the same barrel then the Grendel wouldn't even be close. I'm a grendel fan as well and own two but for hunting there really isn't a comparison. The 270AR handily beats it.

Last edited by SanCalPigHunter; 07/14/13.
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Make the slug .007" larger diameter and I'll take a look.


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Originally Posted by Idaho_Shooter
Make the slug .007" larger diameter and I'll take a look.


I'm not affiliated with ar15performace.com or the gun industry in any way. So tell them not me. I just summed up what i learned and ran the ballistics.

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Originally Posted by SanCalPigHunter
If both tables were from the same barrel then the Grendel wouldn't even be close. I'm a grendel fan as well and own two but for hunting there really isn't a comparison. The 270AR handily beats it.


So you've shot the 270AR?


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You missed chuck hawks and the charts..



Originally Posted by captain seafire
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Originally Posted by ratsmacker
Originally Posted by exbiologist
Sooooo, like a 270 Redding?



No, the Redding is on a .308 case, right? This is based on the .250 AI or .300 Savage case, which would make it equivalent to the old .270 Titus.


Knew it was "revolutionary"... put a plastic tip on that bullet and they'll sell a dozen of them


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MSRHunt Offline OP
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Originally Posted by Steelhead
Originally Posted by SanCalPigHunter
If both tables were from the same barrel then the Grendel wouldn't even be close. I'm a grendel fan as well and own two but for hunting there really isn't a comparison. The 270AR handily beats it.


So you've shot the 270AR?


No like i said i just compiled the info and but the numbers in a ballistic calculator.

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But you said for hunting there isn't really a comparison?

So you are just guessing out your ass, surprising.


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The cartridges that the 270AR is based on require .473 bolt faces. Is there enough meat on a standard size AR15 bolt head to accommodate the larger case head without shearing locking lugs? If the bolt head is larger will it run in a standard upper and bolt carrier? And what about mags- will it run in a .556, 6.8, or 6.5G mag? Or does it require a .270AR mag? Boosting the power in a AR15 can be desirable- there are a passel of existing cartridges that do that now. Thanks for the info.

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MSRHunt Offline OP
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Originally Posted by Steelhead
But you said for hunting there isn't really a comparison?

So you are just guessing out your ass, surprising.


I'm not guessing i'm looking at the numbers. Its all physics. If the barrel velocity is correct then the comparison is pretty accurate subtle barrels differences not with standing. We know what a .277 bullet can do thats well known so no mystery there at all. If we know the muzzle velocity and the BC of the bullet the rest is just math.

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If if's and buts were candy and nuts we'd all have a Merry Christmas.

A 30AR beats them all.


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