AR15 equivalent for .308

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I didn't even think to mention it but you can have your cake and eat it too. There are 2 companies building proprietary AR's chambered in 308 that are near as makes no difference the same size and weight as an AR15

https://dpms-gii.com/full.html

https://pof-usa.com/firearms/revolution-di/

I have handled the DPMS and I must say if someone handed me one in the dark I don't think I could tell that I wasn't holding an AR15. They are quite reasonably priced too. Only downside really is that they are limited in aftermarket support since they are largely proprietary. I am hoping and praying that the aftermarket picks this up and starts to standardize it. I want one in 338 federal.

Isn’t Aero also making DPMS-GII pattern components now too?

I think it’s coming. It would be fantastic if the non-standardized LFAR world would stack hands on the DPMS-GII pattern. The excess weight of AR-10/LR-308’s is a very common complaint.
 
Isn’t Aero also making DPMS-GII pattern components now too?

I think it’s coming. It would be fantastic if the non-standardized LFAR world would stack hands on the DPMS-GII pattern. The excess weight of AR-10/LR-308’s is a very common complaint.

If they are it’s news to me. I searched and couldn’t find anything
 
If they are it’s news to me. I searched and couldn’t find anything

I thought I’d heard that at SHOT - but maybe it was only wishful rumblings, not an announcement. Admittedly, I don’t follow the GII’s much, because I build my own, and there isn’t much option to really do so with the GII format.
 
I thought I’d heard that at SHOT - but maybe it was only wishful rumblings, not an announcement. Admittedly, I don’t follow the GII’s much, because I build my own, and there isn’t much option to really do so with the GII format.

I would guess DPMS probably has patented everything they thought they could defend which will prevent the aftermarket from doing anything with it for awhile.
 
What would I do? (considering my state doesn't allow hunting with .223)

6.5 Grendel if deer hunting was my first priority. 6.8 SPC & 7.62x39 should be considered too.

6mmAR (based off of the Grendel) if varmints were my quarry.

Why? Because these 2 cartridges are not "too far off of the reservation" as far as components are concerned, both have good long range performance and both can effectively harvest medium sized game.

I'm considering a 6mmAR build during 2020.
For the majority of deer hunting the 7.62x39 would be my choice.
Number 2 is a toss up. 6.5 Grendel or 277 wolverine.
For me, a 6mm or smaller has to be pushed well beyond 3000 for me to want to use it.
 
Number 2 is a toss up. 6.5 Grendel or 277 wolverine.
I concur with your #1. Mine #2 is .308, mainly because of combination of accuracy, sufficient punch at ranges well beyond the capabilities of x39 and my personal familiarity with the cartridge (reloading, trajectory and so on). I'm not surprised that people would like to duplicate the performance in AR15 form factor. Then again, like it has been mentioned in this thread, there are lightweight .308 AR platforms like GII so there's no real need to find a substitute.
 
Are there any AR15 uppers chambered for a cartridge that meets or exceeds the performance of the AR10 rifles in .308? I know there is a whole host of choices out there ranging from 6.5 Grendel to .50 Beowulf. Anything match the ol' 7.62 X 51?
I have used 21.5" 308 Vepr on deer, 16" 6.8 SPC shooting 110 Accubond SSA Tac loads, and 18" 308 reloads out of my M&P10 308. About seven total deer taken with these. There doesn't seem to be any "free lunch" as the 6.8 is a noticeable step down from the 308. However that is not to say 6.8 won't work. It would be OK out to 250 or so but is better used at close range to just under 200 yds.
But yeah I guess something 25 WSSM I would be looking at if serious or just bump upnto a lighter weight AR10 in 6 or 6.5 Creed. Smith Wesson makes the performance center 6.5 M&P 10. The Smith&Wesson receivers and carriers are more trim and compact than about any AR10 except the G2 that I have seen but I know there are some new lightweights out there.
Is my M&P10 heavier than an AR15? yes. Is it overly heavy for carry? No. And pretty well balanced.
 
I concur with your #1. Mine #2 is .308, mainly because of combination of accuracy, sufficient punch at ranges well beyond the capabilities of x39 and my personal familiarity with the cartridge (reloading, trajectory and so on). I'm not surprised that people would like to duplicate the performance in AR15 form factor. Then again, like it has been mentioned in this thread, there are lightweight .308 AR platforms like GII so there's no real need to find a substitute.
I should have said AR15 platform.
 
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Bear in mind, a Large frame AR is also built to withstand the rigors of a larger, more powerful cartridge.

So if you are asking a AR15 sized bolt with a larger cartridge comparable to a "308" power level, to last as long as a 308 sized bolt.... you might just consider getting a large frame AR.
 
Bear in mind, a Large frame AR is also built to withstand the rigors of a larger, more powerful cartridge.

So if you are asking a AR15 sized bolt with a larger cartridge comparable to a "308" power level, to last as long as a 308 sized bolt.... you might just consider getting a large frame AR.

The real powerful AR cartridges such as the 30 RAR, those from MDWS, or the WSSM’s all use a proprietary oversized bolt and barrel extension to make them safe with the extra bolt thrust.
 
There seems to be a lot interest currently in .357/.358 AR cartridges. 350 Legend, 9x40mm, 358 Gremlin, 358 Hoosier, 358 Yeti, 358 SOCOM, 358 WSSM. Did I get them all? I haven't seen any 358 wildcats based on the 450 Bushmaster (or 284 Winchester which is the 450 Bushmaster parent). Seems like that would be a good choice for 358 and 375 AR-15 rounds (or even 338, 308 and 270). The 450 Bushmaster bolt is based on the 308 cartridge dimensions and is strengthened for that capacity. It seems that necked down cartridges should feed fine from a single stack 450 magazine. I'm talking about an AR-15 class of large animal hunting cartridges from 200 yards (450 and 375) to 400 yards (358 and 338) to 600 yards (308 and 270).

I can't reload myself, so I am just hoping to stir some interest in those of you who can do such development. But I would love to be able to purchase a 358 "Bushmaster" upper for hog hunting.
 
There seems to be a lot interest currently in .357/.358 AR cartridges. 350 Legend, 9x40mm, 358 Gremlin, 358 Hoosier, 358 Yeti, 358 SOCOM, 358 WSSM. Did I get them all? I haven't seen any 358 wildcats based on the 450 Bushmaster (or 284 Winchester which is the 450 Bushmaster parent). Seems like that would be a good choice for 358 and 375 AR-15 rounds (or even 338, 308 and 270). The 450 Bushmaster bolt is based on the 308 cartridge dimensions and is strengthened for that capacity. It seems that necked down cartridges should feed fine from a single stack 450 magazine. I'm talking about an AR-15 class of large animal hunting cartridges from 200 yards (450 and 375) to 400 yards (358 and 338) to 600 yards (308 and 270).

I can't reload myself, so I am just hoping to stir some interest in those of you who can do such development. But I would love to be able to purchase a 358 "Bushmaster" upper for hog hunting.

First up welcome to the forum.

Next the 450 Bushmaster bolt head is actually weaker than than a standard AR-15 bolt. The lug dimension are the same but there is a larger breach face cut into it making the lug support slightly weaker.

There has been a 30 caliber cartridge based on the 450BM/284 Win, it was call 30 Remington AR and was a very short lived cartridge. It used a propitiatory bolt, barrel extension, upper and funky magazine on a standard AR-15 lower. The 30 RAR bolt would be substantially stronger than a 450 BM bolt. Hence the reason 450 Bushmaster is a 38,500 psi cartridge and 30 RAR is a 55,000 psi cartridge.

You could certainly make a .358 Wildcat on 450 BM/ 284 Win if you wanted but one of the biggest draws to 350 Legend, 450 Bushmaster and similar cartridges is they are legal in straight wall only states like Ohio. A 358 wildcat based on 450 BM would not be legal in those states.
 
So now I have the distinct pleasure of filtering him from my world due to forum features, while it remains apparent I’m still living rent-free in his thoughts. :neener:

By far my favorite feature since the THR re design.

Another option is 7mm-08. 175gr bullets will have just a tad more energy than common 308 loadings. Splitting hairs yes, but it is an option.
 
Look at the 7mm Valkyrie, it's been on the market for a few years now but you don't hear a lot about it. Not sure why, it has the power behind it to exceed many cartridges and it fits into your needs.

Check them out at www.7mmvalkyrie.com plenty of info at their site. It can be used for hunting, target shooting and plinking if that's what you want to do.
 
Another option is 7mm-08. 175gr bullets will have just a tad more energy than common 308 loadings.

I prefer the 7-08 strongly over the 308, but alas, the 7 isn’t possible in the AR-15, only in the 10.

Look at the 7mm Valkyrie, it's been on the market for a few years now but you don't hear a lot about it. Not sure why, it has the power behind it to exceed many cartridges.

Because making brass is a pain in the butt, and it’s a single source proprietary Wildcat. I also wasn’t able to achieve the velocities promised without packing my action with a lot of weight and metering gas to near-zero, and tolerating obvious pressure signs on my brass. When loaded to responsible pressures, I only marginally exceeded the performance of 6.5 Grendel. It’s a cool idea, but it really needs to be proven out to be SAAMI standardized and some bigger mfg’s need to make brass for it before I would go back. It doesn’t achieve what can be with a 7-08 or 308, but it’s pretty impressive for an AR-15 cartridge - if you don’t mind a TON of work to make brass which doesn’t last very long.
 
Varminterror,
Yeah, that's the downside to the 7mm Valkyrie. Most people don't want to make brass.

Did you try different powders and primers on your loads? What brass were you using?

I ended up selling my upper, it was very accurate and worked great, just didn't have the time to get deeper into loading and testing it out.

Still don't know why it doesn't get more attention, it has the potential to be an outstanding round.
 
I apologize if somebody already suggested it, I didnt read every post but doesnt remington make an AR chambered for 7mm-08? That would be ballistically similiar to .308
 
I apologize if somebody already suggested it, I didnt read every post but doesnt remington make an AR chambered for 7mm-08? That would be ballistically similiar to .308
IIRC DPMS made the old LR308 in 7mm-08, Remington may have sold it under the original R-25. The newer DPMS GII (Rem R-25 GII) was slated to have a 7mm-08 in its line up. Alas all of that is for not with the Remington exiting the AR market completely at the beginning of this year.

ETA: Nearly any 308 win gun can be converted to 7mm-08 with a simple barrel swap. For that matter they can be converted to any of the family of cartridges based on the 308 from 22 cal to
45 cal. Some are main stream some are wildcats.

22-243
243 Win
260 Rem
270-308
7mm-08
308 Win
338 Fed
358 Win
45 Raptor

I probably missed a few in there.
 
The real powerful AR cartridges such as the 30 RAR, those from MDWS, or the WSSM’s all use a proprietary oversized bolt and barrel extension to make them safe with the extra bolt thrust.

Nailed it. And as the owner of a 30 Rem AR and a few of the MDWS offerings, I can say with certainty, that the velocities they post are achieved by real barrels and have been duplicated by multiple people. Yes it takes careful load work and a specific set of components but it can be done. And there has only been 1 report of the proprietary bolt/extension failing and it was very obvious they pushed loads to over 70k psi repeatedly and it didn't even fail catastrophically it just stretched and would not function anymore.
 
Nailed it. And as the owner of a 30 Rem AR and a few of the MDWS offerings, I can say with certainty, that the velocities they post are achieved by real barrels and have been duplicated by multiple people. Yes it takes careful load work and a specific set of components but it can be done. And there has only been 1 report of the proprietary bolt/extension failing and it was very obvious they pushed loads to over 70k psi repeatedly and it didn't even fail catastrophically it just stretched and would not function anymore.

I have been very happy with my 358 yeti. It took a little bit to figure out the right brass to use to for it, but its been smooth sailing ever since.
 
What most people who do not do physics calculations very much, yourself included, do not realize is that when we are talking about commonly debated projectiles and commonly debated velocities, difference in mass is typically much larger than the corresponding observed difference in the speed (technically you should not use the term velocity unless you also include a direction).
This explains why the energy of heavier projectiles usually always trumps lighter faster ones when we are talking sporting rifles even though the velocity is squared. There is no Kinetic energy vs. mass debate. There are only people with a glancing view of a physics book who have not fully investigated the situation.
I admit to being one of the vast, ignorant and unwashed hoard of shooters that very rarely spends much time doing physics calculations.

But I do have enough background in agriculture to recognize a pile of BS when I see it.

Your claim that "the energy of heavier projectiles usually always trumps lighter faster ones when we are talking sporting rifles" isn't even true across the spectrum of bullet weights within single chamberings, let alone between cartridges with wildly different maximum chamber pressures and case volume.

Take the 30-06 as an example. We'll compare maximum energies between the highest velocity loads listed for the 220 grain bullet and the 150 grain bullet using Hodgdon's online reloading database.
We'll then take the resulting weights/velocities and plug 'em into an online calculator to see which has the most kinetic energy.

First is data for the 220 grain 30-06 bullet.

Screenshot_20200209-200457_Opera.jpg

Next is data for the 150 grain 30-06 bullet.

Screenshot_20200209-200311_Opera.jpg

Now we run the numbers through an online calculator.

Screenshot_20200209-200025_Opera.jpg
Oops...

Looks like the 150 beat the 220 by almost 150 foot pounds.

So why do you claim: "the energy of heavier projectiles usually always trumps lighter faster ones when we are talking sporting rifles"?


PS: In case you're unaware, when the term "muzzle velocity" is used, the direction is commonly understood to be "away from the butt plate", or more precisely, "away from the bolt face".
 
I prefer the 7-08 strongly over the 308, but alas, the 7 isn’t possible in the AR-15, only in the 10.

That was something I was looking up, whether it went into a standard AR15 or needed the 10. Logically knowing the 7mm-08 is a necked down 308 so AR-10 but didn't know for sure. Still, 7mm bullets can be quite the advantage. Especially to a handloader.
 
MDWS offers 90% of 7mm08 performance from the AR-15 it's called the 7mm Valkyrie AR. I'm a HUGE 7-08 fan and a MSR fan and I had to have one and my 7mm Valkyrie AR is my favorite MSR.
 
An AR15 is limited to cartridges with an overall length of 2.300” or less due to the size of the magazine well. Anything 308 length such as 7-08, 243, 6.5cm ect... has to go in an AR10. For those that haven’t compared both an AR10 is a much larger and heavier platform than an AR15.
 
An AR15 is limited to cartridges with an overall length of 2.300” or less due to the size of the magazine well. Anything 308 length such as 7-08, 243, 6.5cm ect... has to go in an AR10. For those that haven’t compared both an AR10 is a much larger and heavier platform than an AR15.
You should check out the M&P10. I have one, and previously another. They both are great shooters. With American Defense mount and Leupold 2-7 scope doesn't feel too heavy. My current rifle shoots PMC X-Tac really well. I subbed in a Geissele trigger for an improved pull.
 
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