6.8 SPC AR 15 Questions

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Hit a deer at 300yrds, the difference in 60grns and 120 becomes very clear.
I dont think so.
I would take the 300 yd accuracy of a 60gr. Partition launched at 3000 fps over a light for caliber and slow 120gr. 277 launching at only 2550 any day.
 
"with the .270win which has already been fading in popularity in the last two generations, and its parent case is an obscure, obsolete cartridge"

The .30-'06 is obscure and obsolete?

I don't question at all that 6.5 grendel is superior, for all the reasons you mention - I totally agree. My main point was that *in spite of* its inferiority (in my view), the 6.8 spc is still to this day, in 2018, more popular than 6.5 grendel, for some reason, with my "proof" being that recent manufacturer (whose name slips my mind - believe it was on a 2018 SHOT show video I watched) coming out with an MSR chambered in 6.8 but not 6.5. When I say more popular, I mean overall, not necessarily in one neck of the country or another... I don't think these big makers are going to make as large of a mistake as misreading the country as a whole, as to what actual demand is. They don't want to miss sales.
 
@DannyLandrum - the 6.8’s parent case is obsolete and obscure.

.30-06 really isn’t doing so well these days itself, for that matter.

And the motivations of one particular manufacturer aren’t good guidance of overall market penetration. Lots of manufacturers have lots of reasons for launching the products they launch, not all of them are accurate reads of the current market.
 
I understand .224 Valkyrie is a necked-down 6.8 case, which means brass and magazines shouldn't be an issue in the future for 6.8.
 
We’ll see how the Valk takes off. The Nosler wasn’t the industry revolution it had promised, and the Valk doesn’t seem to be taking off any faster.

We can pretend .277” cartridges and the 6.8 case is going to be as popular in the next decade as they were in the last, compared to 6.5mm cartridges and the proliferance of the x39 case... I try to be more realistic.
 
30-06, .270, every belted magnum...yes they are all fading a bit. The reason is that bullet technology is steadily improving. People are finally able to truly do today in .308 what people in the 60s were doing with 30-06, because bullets are better. That slight velocity jump doesn’t matter as much now because bullets reliably perform better at any range. The really sad thing is that the technology is there, but is not being applied to certain diameter bullets such as .277, or .284. There is absolutely no way that there is enough practical difference between a 6.5 and a 6.8 diameter bullet that the technology won’t work and do as well in a proportionally similar bullet. Same goes for .284 and .308 diameters...using the same tech as even the .243, so if it works on 243 and works on .308 then it works in between. Give me a better .277 bullet to use in 6.8 and/or .270 and I will gladly buy them by the thousand.
 
If I were going to get one it would be the grendel. I've no interest in shooting anything with expensive brass in a semi auto and not really interested in hunting big game with an AR15, but I researched them both a good bit because I was interested in them for a contender carbine.
 
I'd go 6.8. There is a plethora of factory ammo to choose from, and it's reasonable. Just tonight I was reading on another board a new grendel shooter was lamenting ammo availability. He found choices very limited online, and all of that was sold out. He was told to stock up when he can. I know my LGS's carry 6.8, I have never seen the grendel on a shelf yet.
Another thing to consider is factory 6.5 is loaded to the max. You can't reload and squeeze a little more out of it, it can break bolts as is. The modern 6.8 SPC II still has leeway and can be loaded hotter without issue. Hot enough to outshine 6.5 at any ethical hunting range.
 
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@DannyLandrum - the 6.8’s parent case is obsolete and obscure.

.30-06 really isn’t doing so well these days itself, for that matter.

And the motivations of one particular manufacturer aren’t good guidance of overall market penetration. Lots of manufacturers have lots of reasons for launching the products they launch, not all of them are accurate reads of the current market.

Not true.

Sorry, the .30-06 and the .270 is alive and well as shooting ammunition. Some people are even surprised that the 'umble .30-30 is still a top ten selling rifle cartridge depending on which list you choose to follow. Certainly still in the top twenty. A brief perusal of Wally World or any large sporting goods store and determining shelf space and variety for a given cartridge gives an indirect measure of a cartridge's popularity. And you find the .30-06 and .270 well represented. Grendel and 6.8 SPC are just a blip. Certainly .223 and 7.62x39 are popular and probably shot more in bulk but may not represent value/profit to manufacturers compared with the other cartridges bringing higher margins. Pistol ammunition sales and count apparently top even the .223.

For more see, http://www.chuckhawks.com/readers_choice_rifle_cartridges.htm

2015 cartridge selling data http://www.chuckhawks.com/best_selling_rifle_cartridges.htm

NRA article discussing Federal Ammunition's most popular rounds https://www.americanhunter.org/articles/2015/12/20/america-s-most-wanted-ammunition/

I found half a dozen other lists from publications or blog postings that basically give the same information about rifle cartridges with boring regularity. The only outlier was Lucky Gunner's 2013 data that may or may not be representative of the market as a whole--not too many people shoot bulk .270 or .30-06 versus pistol rounds or .223/7.62x39. Bulk ammo buyers (apart from government are relatively small in number) are probably heading to places like Lucky Gunner and buying in bulk while the more numerous Joe Sixpack hunter types picks up ammo at the big box store. Shipping usually kills an individual buying a few boxes online for a round readily available in stores. That is why I find the federal information more useful than Lucky Gunner as well as the Chuck Hawks and other magazine surveys of readers.

Regarding parent cartridges, it only matters if the brass is not made anymore for a cartridge where you have to do case forming.

During the heyday of the Big Ammo trio of Federal, Winchester, and Remington, odd chamberings for bolt rifles were at the mercy of those companies and required careful attention to parent cartridges as the loaded ammo could vanish based on rifle sales. The brass market is far broader than it used to be with boutiques brass lines such as Starline, Nosler, Hornady, etc. and imports like Lapua or Prvi challenging the big three. Boutique reloading outfits are also now in existence. I also suspect that the internet now allows concentrating customer demand for less favored cartridges on a few on-line sellers rather than persuading big box retailers or gun stores to carry it.
 
I dont think so.
I would take the 300 yd accuracy of a 60gr. Partition launched at 3000 fps over a light for caliber and slow 120gr. 277 launching at only 2550 any day.

Having taken game for over a decade with the 60 partition, there’s nothing that I would call “accurate” about what it does at 300yrds compared to a 120 SST or 110 Barnes in the 6.8.

Don’t confuse velocity with accuracy or precision.

Check your penetration efficiency as well - the SD for the 60 Partition is only 0.171, to the 120 SST’s 0.223.

This comparison ain’t a thought experiment for me - I’ve been taking deer and hogs with both in question long enough to know the difference in the field. Both will kill a deer at 300yrds, but one makes your legs tired afterward.
 
I was a contributing researcher making a lot of those phone calls to establish the market trend lists put out in 2015 (very en vogue topic at the time).

The chuck hawks list is a poor indicator of future market, as it focused on AMMUNITION manufacturers’ sales volumes, which is a measure of past market trends. When you compare that with the data I and others compiled from the firearms manufacturers - which is indicative of future ammunition and component sales - the list was VERY different. The belted mags didn’t appear in the top 25, .30-06 and .270 weren’t top 10. 308 and 223 lead the pack, 6.5 creed was surprisingly low for the marketing expectation at the time, between 6th and 8th for most manufacturers. Although two did mention - if we’d made more to sell, we’d have sold every one...
 
Do you have any numbers of rifles sold in different calibers year over year? I think there has been a huge influx of people buying rifles in the past 10 years for purely recreational purposes and that is changing things since they are obviously not buying 30-06's to plink at the range. For the vast majority of older people I know, shooting a centerfire rifle for recreation is a concept that doesn't even exist for them. I would bet even though the percentages have declined the actual number of rifles sold every year in 270 and 30-06 hasn't changed that much since there is relatively static demand for "deer rifles". I know the local stores around me sell cases and cases of 270 and 30-06 axis's and the like. Those two are still the most common rifle on the shelf by far here.
 
Having taken game for over a decade with the 60 partition, there’s nothing that I would call “accurate” about what it does at 300yrds compared to a 120 SST or 110 Barnes in the 6.8.

Don’t confuse velocity with accuracy or precision.

Check your penetration efficiency as well - the SD for the 60 Partition is only 0.171, to the 120 SST’s 0.223.

This comparison ain’t a thought experiment for me - I’ve been taking deer and hogs with both in question long enough to know the difference in the field. Both will kill a deer at 300yrds, but one makes your legs tired afterward.

Yeah. I really liked the football size diameter hole in the cooyotes neck at 240 yds out of my 223. He was loping away uphill when the partition toppled him.

OTOH I didn't really like my buck casually walking over a hill after I shot him behind the shoulder with my 6.8 at 150 yds. and humping up down there waiting for me put him out of his misery with a second shot.

A 60 gr. Partition probably would hsve killed quicker.
So on the contrary, I would rather shoot any game I'd be so inclined at any range with my 223 and 60 gr. Partition.

Funny how the 6.8 crowd will say all day long 556 is way better than a 762X39 then turn around and say 6.8 is way better than 5.56.
Do yourself a favor and put a 6.8 case right next to a 7.62X39 case and then you will see they really are the same thing. Wikipedia lists the case capacity of 6.8SPC as 34.8-36.9 gr. H2O, while 7.62X39 (which also fires your magic 120 gr.) as 35.6 gr. H2O. And many more critters, of all kinds, have been killed at longer ranges with 5.56 than 6.8 ever will. And that is a fact.

So the 6.8 really is akin to the Emperors new clothes.
 
After going through that data collection a few years ago (which just captured ONE year), I would say you have it nailed. The average guy buying a rifle is NOT buying a deer rifle, or a rifle meant for hunting at all. Hunting is on the decline, and has been. Recreational plinking and “long range shooting” (whatever that means to the individual buyer) are the modern justification for buying rifles.
 
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Do yourself a favor and put a 6.8 case right next to a 7.62X39 case and then you will see they really are the same thing

Capacity, bullet weight, and velocity... Except one is shooting a bullet with a BC of .400 instead of .300, and an SD of .224 instead of .180...
 
I don't know how big the deer are where you guys live but there is no freakin way I'm shooting deer at 300 yards with a 60 gr bullet. There is just no reason for that non sense.
 
Capacity, bullet weight, and velocity... Except one is shooting a bullet with a BC of .400 instead of .300, and an SD of .224 instead of .180...
And here is another fact: That tiny little 100 gr. .243 Win. is way better than a 6.8, though not really in the world of AR's.
The two deer I shot with 6.8 I saw it do nothing a fast 60gr. Partition could not do. And in my view the 60 gr. Partition probably would have actually performed better in terms of terminal performance. The reduced recoil of the 60 gr. allows better shot placement, while the flatter trajectory allows better hits on coyotes and confidence in extended ranges.
 
60 partition or 120sst is of little consequence under ideal conditions. Put lead where it's intended and the critter shuts down quickly. The biggest thing I would consider between the two is what happens when a bullet fails to perform as intended. I hunt woods, and even in open country there is scrub brush here and there that animals use for cover. When you smack a small treelimb between you and the critter what does that bullet do? The answer is pretty wide open but the two best and most likely options are that the bullet deflects and is a clean miss, or it hits square enough to just punch through the limb shedding velocity and deforming. Worst case scenario is you poke a hole with a damaged bullet that doesn't expand. You have a .223 hole or a .277 hole. Which one bleeds out faster? Cross section of the .223 is about .04 inches where cross section of the .277 is as about .06 inches. Thats a significant difference in bleeding out and a significant difference in blood trail being left.
 
60 partition or 120sst is of little consequence under ideal conditions. Put lead where it's intended and the critter shuts down quickly. The biggest thing I would consider between the two is what happens when a bullet fails to perform as intended. I hunt woods, and even in open country there is scrub brush here and there that animals use for cover. When you smack a small treelimb between you and the critter what does that bullet do? The answer is pretty wide open but the two best and most likely options are that the bullet deflects and is a clean miss, or it hits square enough to just punch through the limb shedding velocity and deforming. Worst case scenario is you poke a hole with a damaged bullet that doesn't expand. You have a .223 hole or a .277 hole. Which one bleeds out faster? Cross section of the .223 is about .04 inches where cross section of the .277 is as about .06 inches. Thats a significant difference in bleeding out and a significant difference in blood trail being left.

That just it, I don't have any problem killing deer, the problem is finding them afterward. Our hunting land is a mix of mature oak woods and sloughs with tall grass and red willows. Down in the sloughs in the grass you can't see deer in there unless you are 5 yards from them. Even when you shoot deer coming out of the slough into the woods they are programmed to make it to the thickest cover they can so even heart shot they make a b line straight for the thickest cover they can get to. If you don't have a blood trail it can take hours to find a deer that went 100 yards. Thats why I've come to the conclusion that for where I hunt I want the heaviest and widest bullet I can comfortably shoot so I get an exit hole that they will actually bleed out instead of just filling up there chest. Where we hunt if you have a deer go 200 yards with no blood trail your chances of ever finding it are about 10%.
 
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