Home Forums Hunting & Shooting Hunter's Campfire 270AR SPR (New AR-15 cartridge coming this fall)

how old are you, I'm welling to bet pretty young otherwise you'd be able to comprehend what others here are trying to tell you.

You got me i'm still wet behind the ears but you taught me well and i now know old crusty walmart beer belly hunters get better ballistics just because of experience. Blah hahaha....

You wanted to talk about calipers and ballistics. I asked you multiple questions about the cartridge and its ballistics.

But you won't answer me. That's because you don't have any answers that you can't read off of a chart.

Jesus SanCalPigPhucker are you this stupid in real life, or do you just play it on the internet?...

One more time and maybe you will understand it.
You have no personal experiences with the round you are talking about, and all your speculation is based on hype from the rounds creators. Which means exactly jack chit in real life.
Until there is some actual data and testing done by people who don't have a stake the success of the cartridge its no [bleep] game changer.

don't drink and i run all my hand loads over a chrono so i don't have to guess. i've killed hogs with everything from a 22 to my 300rum, lots with my AR shooting 223. bullet construction and shot placement trump velocity.

...or maybe just ask the folks over at ar15performance.com to chip and buy you a pair of these:

well, those of us who've been handloading for 30+ years have seen more than a few new wonder cartridges arrive with great fanfare. Some have stuck, some have faded away. New isn't necessarily bad, but it's not automatically good, either. Lots of super-duper wildcats have arrived with great performance numbers, until people realized they were loaded really, really, hot.

There's guys here who have killed deer with 6.8 SPC's; the military has issued it, so lots of real world data says it works as advertised. If it's going to be a few months before anyone even has barrels available for the 270AR, then a little skepticism is warranted, especially when like me I've already bought a 6.8 SPC bolt & barrel.

And us old timers also remember that a decrepit old round, the 6.8 x 64 (aka .270 Win) will drive 130's easily over 3100 fps, maybe as much as 3200 fps, just to put things in perspective

But hey I'm open minded, if someone wants to trade me a 270AR barrel & bolt for my 6.8 SPC parts, and let me be a Beta tester, I promise to be open minded

The 6.8SPC was produced by Remington from a request of a Special Forces Unit. All military requests to industry are outlined in what's referred to as "requirements". These requirements are detailed and force the contractor work with them. The 6.8SPC being for a military application had a requirement to hold a specific number of rounds in the magazine. This magazine requirement limited the brass size of each case. Remington needed to design a round within these limitations. The smaller brass size limited the amount of powder grains that could loaded and therefore the velocity of the projectile. Taking the same bullet the .277 (270) without the rounds per magazine limitation opens up the possibility for large case size and therefore more powder and higher velocity's. In other words nothing surprising about getting 200fps higher than the 6.8spc which is designed as a military round NOT A HUNTING cartridge. The wildcat case (based on the 6.5 lapua) will hold 10 more grains of powder and therefore 200fps improvement is a conservative number. There's no reason to believe that the developer is faking numbers but I think hes probably being conservative in his estimates.

I had not said it before, but after this post, maybe the forum you came from is a better place for you to be.

Hell this one even has an AR type specific subforum but here you are brand new and all, telling folks that have run the AR probably before you were born, how it all should and will be. Never mind actually having done it.

The 6.8SPC was produced by Remington from a request of a Special Forces Unit. All military requests to industry are outlined in what's referred to as "requirements". These requirements are detailed and force the contractor work with them. The 6.8SPC being for a military application had a requirement to hold a specific number of rounds in the magazine. This magazine requirement limited the brass size of each case. Remington needed to design a round within these limitations. The smaller brass size limited the amount of powder grains that could loaded and therefore the velocity of the projectile. Taking the same bullet the .277 (270) without the rounds per magazine limitation opens up the possibility for large case size and therefore more powder and higher velocity's. In other words nothing surprising about getting 200fps higher than the 6.8spc which is designed as a military round NOT A HUNTING cartridge. The wildcat case (based on the 6.5 lapua) will hold 10 more grains of powder and therefore 200fps improvement is a conservative number. There's no reason to believe that the developer is faking numbers but I think hes probably being conservative in his estimates.

According to Mule Deer's 1/4 rule, the 270 SPR should be capable of around 200 fps increase at similar pressure levels compared to the 6.8 SPC. This is using the case capacity figures you quoted.

According to Hodgdon 6.8 data, a 110 Vmax is capable of 2690 fps with a 24" barrel (with 30 grains of IMR 8208) . Conservatively estimating a 15 fps loss per inch, that will be around 2610 with an 18" barrel at similar pressure levels.

So if your round is capable of a 200 fps increase, we are looking at just over 2800 fps with 110s at similar pressure levels.

This is if everything goes according to plan. The increase in case capacity may bump up the best powder choice into a slower bracket, and IMR 8208 may not be ideal. In face, I'm betting it will be on the fast side when it comes to 130 grain bullets, but that's just a postulation.

Read my above post and you will see its not hype and rather expected. Nothing surpriseing about getting 200FPS out of a AR shooting .277 cal bullets. Its about time someone did it. You just need a little fatter case that will hold more powder. its not a large capacity mag tactical type rifle but rather a AR-15 hunting rifle that will hold less bullets per magazine.

5.56, 264LBC/Grendel, 6.8x45GPC, 270AR, 6.5x47, 308


The bolt is a 800 serices bolt made from stronger alloy.

200 fps gains me............what? More recoil/noise for my 8 year old son, great!

I understand that everyone has a different application for their hunting ARs. I'm not generally using mine (for deer) past 300, and that's not frequent. The 6.8 does the job with no fuss.

I'm good.......

George

Using another one of "The Rules" we see that an increase from the 110 to a 130 grain bullets, should result in a 9% decrease in velocity. At 2800 fps, that means a 254 fps decrease, when increasing from a 110 to a 130 grain bullet.

So going by a comparison with published 6.8 SPC data, you should see 2550 with a 130 in an 18" barrel with the 270 SPR. I'll be generous and say 2600, as you may run into a better suited powder.

Of course, if you jump the pressure, the sky is the limit....

Most hunting bullets require a velocity of 1800FPS to expand. Adding 200FPS makes the actual effective hunting range longer. Look at the graphs i posted keeping in mind the 1800fps impact rule and you'll see it gives you more than 100 yards more effective actual hunting range. In other words deer you had to let go are now in play. Deer that were already in range are now being hit with more energy than before.

you really havent done much actual hunting.....put down Field and Stream and actually get out in the field.....

Yeah, I have no problem grasping the theory of extra yardage and more energy at closer range. My point, again, is that IMO it isn't necessary.

The 6.8 has no issues with deer past 300. In my AO, I very rarely see shots like those. If I do, I can spin the extra with no worries. I'm certainly not letting Connor, my son, take those shots at this point so it's irrelevant there.

So, again, what does it offer me besides more recoil/noise for my boy to contend with?

Ok, just ran the 6.8 SPC through Quickload. At Max SAAMI pressure, it looks to fall just short of 2400 fps with a 130 Berger.

I noted that the data I quoted earlier fell a bit short of SAAMI max, so the 2600 with a 130 is probably in the ballpark for the 270 SPR.

Getting back to the quickload data....Add the 200 fps the 270 SPR is capable of, and we see around 2600 with a 130 in an 18" barrel. So I sorta confirmed the data I came up with using "The Rules". If I'm off on my math somewhere, someone please correct me, as I'm borderline retarded when it comes to math.

That is A LONG ways from the 2775 being quoted with a 20" barrel.Of course, if a guy was using "some guys" 6.8 SPC internet data, and not pressure tested data, it's probably doable.

I remember a guy on here a couple years ago who developed a super improved 25-06, and was disappointed when he couldn't beat the random person on the internet's data he had found on reloader's nest. For all he knew, the guy with the 3600 fps with a 100 grain bullet out of a 25-06 Ackley that he was trying to beat had sent the bolt back through his face the next pull of the trigger.

What I'm saying here, is that one must compare to published, pressure tested data, not internet pressures.

SanCal, will you answer any of my questions?

It seems like you're only wanting to argue.