Barrett are some of the best mags I have used. They are a bit larger but hold 30 rounds. You can usually get them for half off.Originally Posted by hawk
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Barrett are some of the best mags I have used. They are a bit larger but hold 30 rounds. You can usually get them for half off.
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Try ASC 6.8 mags. They hold 26 rounds (lists 25rds, but it's 26) and still allow for administrative / tactical re-loads (aka inserting a full mag with the bolt closed on a chambered cartridge). On an open bolt, they load to 27rds. They also allow an OAL of 2.316 which is awesome for re-loaders. They were the only game in town for good 5.45 mags back before 7N6 was banned (had a 5.45 training upper for cheap ammo) which is how I learned about them. Build quality is very good, better quality than the D&H ones which are literally manufactured in the same town my father lives in WI (he bought some of each but also prefers the ASC's).
As for wounding, in the legitimate studies I have seen, the terminal performance of 6.8 mm projectiles actually does outperform that of 6.5 mm projectiles even when bullet construction is identical. Take at look at some the real world testing that includes performance through intermediate barriers, hunting kills on medium and large game etc.:
https://ndiastorage.blob.core.usgovc...tl/Roberts.pdf
https://ndiastorage.blob.core.usgovc.../Zhou19394.pdf
http://www.frfrogspad.com/68spc.htm
https://68forums.com/forums/showthre...elt-elk-vs-6-8
Couple of points to note the differences between 6.5 Grendel and 6.8 SPC:
- While aerodynamic efficiency (low drag projectiles) is a boon to maintaining energy and increasing long range accuracy by reducing windage and drop, it NEGATIVELY correlates to terminal performance upon impact. Bigger bullets simply leave bigger holes and have HIGHER drag while passing through the target. In real testing, the slight velocity differences seem less important to terminal performance than the caliber differences. I suspect there is a threshold of force per a square inch exerted on the bulllet that allows more ideal expansion of the slightly bigger diameter 6.8mm and 7mm projectiles over their 6mm and 6.5mm counterparts.
Military ballistic research specifically indicates the larger diameter projectiles had better terminal performance, but the smaller diameter projectiles had better accuracy at longer ranges going up and down the scale. The key is to balance drag losses (aka remaining KE) / accuracy with terminal performance (aka upon impact and while traveling through the target). This has as much to do with projectile shape / size as it does with construction. The bigger the bullet diameter, the better terminal effect it had. The smaller the bullet diameter, the better accuracy it had (all of them were tested from the same .30 cal parent case). 6.8mm projectiles provided the best balance, despite not being the absolute best at any one metric compared to 6mm, 6.5mm, 7mm and 7.62mm.
- 6.5 Bolts ARE inherently weaker because of the bolt dimensions. While there are ways to improve their durability, you can do the same thing to a 5.56 or 6.8 bolt and it will always be stronger than a comparable 6.5 bolt. Weather it's enough to matter for your application is for you to decide (scroll down to "What is my problem with the Grendel?" section): https://www.ar15performance.com/faqs I will say that while they are weaker, I'm not 100% convinced it's enough of an issue to be the "deciding factor". But bolt durability is better with small frame AR cartridges other than 6.5 Grendel.
- 6.8 load choices are much more plentiful in terms of selection / variety. There are simply more options out there for both re-loaders and those who shoot factory loads. 6.5 projectiles and factory loads seem to be more heavily focused on match target loads or affordable plinking loads rather than hunting / self defense (aka premium SP, Bonded HP, Monolothic SCHP).
Hornady's Load Data when normalized for the same barrel lengths (16") are as follows (a known comparable standard):
For 120gr SST in 6.8 SPC
2460 FPS / 1612 ft-lbs @ Muzzle
1863 FPS / 925 ft-lbs @ 300 yds
1524 FPS / 619 ft-lbs @ 500 yds
For 123gr SST in 6.5 Grendel (data normalized for 16" barrel length, original data is listed for 24" barrel lengths)
2390 FPS / 1560 ft-lbs @ Muzzle (-52 ft-lbs over 120gr SST 6.8 SPC)
1899 FPS / 985 ft-lbs @ 300 yds (+60 ft-lbs over 120gr SST 6.8 SPC)
1604 FPS / 703 ft-lbs @ 500 yds (+85 ft-lbs over 120gr SST 6.8 SPC)
Can both cartridges be shot much further? Sure. But are they terminally effective at distances that far? Probably not given how low the KE is already at 500 yards for BOTH cartridges. Expansion of hollow point projectiles typically doesn't occur at velocities below 1600 to 1800 FPS (depending on bullet construction, mass and diameter). While there are plenty of real world examples of people shooting 6.5 Grendel out to 800~1000 yards it is pretty meaningless in terms of actual application other than bragging rights, banging steel gongs or punching holes in paper. Lethality is drastically decreased at those ranges, no expansion will occur and technically at those ranges, 6.8 will literally leave a bigger hole than 6.5 because well...it's bigger diameter! So other than a slight advantage in ease of use (less drop / drift) at extreme ranges, what practical advantage does it have over 6.8? None that I can see. But 6.8 does have some real world applicable advantages are more realistically usable ranges!
6.5 Grendel is NOT a long range cartridge and neither is 6.8 SPC. While 6.5 Grendel does have some small advantages in terms of accuracy at longer ranges due to it's higher BC, 6.8 seems to provide better terminal performance at practical ranges where both cartridges are considered effective as per the 2008 Roberts report and other data linked above. A true long range cartridge would be .338 Norma Magnum (one of the Army's new squad level MG's is now chambered in that round) that can defeat armor at up to 1000 yards with some loads: https://nationalinterest.org/blog/bu...-future-124241
Both 6.8 and 6.5 Grendel do offer substantial performance advantages over 7.62x39mm, which unfortunately due to the short and fat projectile, looses energy much faster and by 500 yards, Hornady 123gr SST 7.62x39mm is down to just 1033 FPS / 291 ft-lbs. Less than half of either American implementations of the "intermediate cartridge" concept. I ended up with 6.8 SPC because the data above (as well as other data I have acquired) is well documented and actually shows verifiable advantages. 6.5 Grendel does indeed have velocity advantages at longer ranges, but they aren't enough to present a significant advantage at those velocities and for practical purposes, I think 6.8 SPC is better rounded in terms of over all practical application even if it isn't the best at long range paper / steel.
Last edited by win&legend; 03-10-20 at 15:17.
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BTW i run a 16" 3R Hybrid Scout barrel from ARP with a Precision Armament Hypertap break using the AA mid-length piston setup (P-series micro adjustable gas block), AA's low mass NiB carrier with a JP SCS-15 buffer set up for 3oz (3 steel weights). I had to drill out the ARP gas port to 7/64 (up 2 sizes) to achieve fully reliable cycling even when not shouldered (CQB applications for a 16" carbine, run the butt stock up over your shoulder and pull in, it's a common technique for very close quarters with longer guns). Recoil is exceptionally light (BTW I don't like compensators, I originally tried the hypertap with 4 of the 6 top pilot holes drilled out as per their tuning guide, it was great for prone supported bench shooting, but I did NOT like the feel when standing for practical shooting, so I ended up ordering another one and left it un-compensated).
Last edited by win&legend; 03-10-20 at 15:20.
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Did you really just say that bigger bullets make bigger holes in reference to .264 vs .277? Technically you may not be wrong, but....
RLTW
“What’s New” button, but without GD: https://www.m4carbine.net/search.php...new&exclude=60 , courtesy of ST911.
Disclosure: I am affiliated PRN with a tactical training center, but I speak only for myself. I have no idea what we sell, other than CLP and training. I receive no income from sale of hard goods.
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We have all seen the posts 10,000 times "The 6.5 Grendel bullets have a higher SD so they will penetrate better". Well those advertised SD figures only mean something if the bullet NEVER expands, never changes shape. Personally I like bullets that expand properly when hunting game" bigger hole more damage". I would not use a bullet that does not expand on game and many states have laws prohibiting use of FMJ bullets.
Some of the bullets people are using in the Grendel were made for the 260 and 6.5x55 and they will not expand properly when shot at the slower speeds that the Grendel can push them especially at the longer distances the guys are claiming you can shoot deer at(600yds). IT would be the same if people were using 140-150gr .277 bullets made for the 270 Win. Of course some of the lighter weight bullets like the 123SST were made specifically for the Grendel and will expand properly.
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Technically it is correct. Every little bit helps lol. Realistically I would not expect to be able to measure a difference in the permanent wound channel between a non-expanded 6.5 or 6.8 missile. They would be indistinguishable.
However the actual data does prove that the very small difference in diameter does impact terminal performance in some surprising ways, especially intermediate barrier penetration. One would not expect the small 0.3mm diameter difference to matter, but in cases like hitting auto glass at 100m, 6.8 OTM clearly outperforms 6.5 OTM as just one example. This theme seems to repeat when looking at terminal performance where real advantages are seen.
Take a look at the 2008 Roberts NDIA report to the US military on the test findings from the original development. They tested 6mm, 6.5mm, 6.8mm, 7mm and 7.62mm projectiles in the same parent case (.30 cal Remington). 6.8 provided the best overall balance of terminal performance, accuracy and reliability of any of the test variants.
My point is still valid however that 6.5 Grendel is NOT a long range cartridge. It's a far cry from 6.5 Creedmoor or the significantly more powerful cartridges like .338 Lapua Magnum or .338 Norma Magnum etc. That's often cited as an example of why 6.5 is "superior". Their KE is nearly identical at ranges where velocity is actually high enough to cause expansion upon impact. 6.8 was developed for engagment ranges of 0 to 500 yards. Can you shoot i further? Sure, but it's effectiveness on target is severely diminished.
The ranges where 6.5 Grendel has a meaningful velocity advantage are substantially below the expansion threshold of either, thus it's generally meaningless unless you get a CNS or vital organ hit on the target (in which case non-expanding missiles are still highly lethal). Either way, it doesn't seem to be a meaningful advantage given that both cartridges can still deliver enough energy to be lethal IF and ONLY if a CNS or vital organ hit occurs. Otherwise wounding is severely diminished in both cases.
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I'm going to throw a plug in for the .277 Wolverine. This is a wildcat cartridge based on a cut down 223 Remington and uses 6.8 SPC bullets.
It is similar in design concept to the 300 Blackout but coming at the idea from a different angle. As where the 300 originated as a way to shoot a heavy subsonic bullet with supersonic as a secondary application the 277 started out as a supersonic that can also be loaded with subs.
Being based off the supersonic idea first, the 277 has a longer case and more powder capacity than the 300. It is best used with 90-110 grain bullets although 130 grain bullets can also be loaded to pretty good speeds. I have an upper built with a 12.5" barrel and can push a 90 grain Speer Gold Dot to 2,300 fps from this SBR. People with 16-18" barrels are reporting 2500-2700 fps in most cases.
Subsonic bullets get a little tricky since most easily available 270 bullets top out at 150 grains. Even so, I have been able to get reliable performance from a 150 with my AAC suppressor attached. I haven't tried loading 150's to supersonic speeds. My guess is 1700-ish fps. Maybe not that good since the long bullet soaks up case capacity.
So what good is the 277 WLV? It uses readily available (and good) bullets like the aforementioned Gold Dot and Nosler 90gr Bonded. Being that these are slightly smaller in diameter than .30 bullets the 277 stacks properly in a USGI mag. It yields performance somewhat similar to the 6.8 SPC but doesn't need a new bolt and gives a full 30 round mag capacity.
Constructor had the idea first but didn't really do much with it as far as I know. Later, Mark Kexel asked if he could run with the idea and has done pretty well with it. He was working on getting it SAAMI approved but I don't think much has happened in that regard. Brass can be made from chopping 223 cases or it can be bought from Hornady or Starline.
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“The rifle itself has no moral stature, since it has no will of its own. Naturally, it may be used by evil men for evil purposes, but there are more good men than evil, and while the latter cannot be persuaded to the path of righteousness by propaganda, they can certainly be corrected by good men with rifles."
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The .277 WLV really loses more than 100 fps per inch?? From what I've seen, 2700 fps is the norm for the 90gr rounds from a 16" barrel. I would think that from a 12.5" barrel the velocity would be closer to 2550 to 2600 fps.
Those who beat their swords into plowshares will plow for those who do not.-Ben Franklin
there’s some good in this world, Mr. Frodo. And it’s worth fighting for.-Samwise Gamgee
Senior Member
When I get back home I'll check my chronograph notes. Going from memory here.
Edit: or we can just review my existing 277 WLV thread:
https://www.m4carbine.net/showthread...nd-Experiences
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Last edited by Tokarev; 03-10-20 at 22:31.
“The rifle itself has no moral stature, since it has no will of its own. Naturally, it may be used by evil men for evil purposes, but there are more good men than evil, and while the latter cannot be persuaded to the path of righteousness by propaganda, they can certainly be corrected by good men with rifles."
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Question, if we are criticizing the 6.8 SPC for its performance at longer ranges compared to the 6.5 Grendel (hence why the original thread asked if anyone still used 6.8 SPC instead of Grendel), why would we want to go with a wild cat that produces lower muzzle energy just to spare the cost of a new bolt ($70) and a few mags?
I'm not seeing an advantage in .277 Wolverine over 6.8 SPC or 6.5 Grendel. 2500 FPS to 2700 FPS from a 90gr in a 16" to 18" barrel is significantly less than what can be achieved with hand-loaded 6.8's that can break well over 3,000 FPS at those weights and barrel lengths.
There factory 85gr 6.8 loads pushing 2950 FPS from a 16" barrel (SSA 85gr Nosler E-tip) or 120gr SST loads from Hornady pushing 2460 FPS from a 16" barrel. 6.8 Mags, 6.8 Bolts, brass and barrels are plentiful and very affordable.
Known 6.8 Mags:
C-Products AR-15/M16 6.8 SPC MAGAZINES available in 5, 10, 20 and 28 rd capacity at Brownells or from C-Products directly
Precision Reflex Inc. 6.8mm SPC/.224 Valkyrie/.22 Nosler Waffle Magazine available in 5 and 10 rd capacity at OpticsPlanet
E-Land 6.8 SPC Steel available at OpticsPlanet, CheaperThanDirt in 10 and 25 rd capacity
ProMag Ruger Ranch Rifle 6.8 SPC Rifle Magazine 10 rd available at OpticsPlanet or from Ruger directly
ProMag AR-15 Magazine 6.8 Remington SPC in 27 rd capacity at CheaperThanDirt
Ruger SR-556 25 Round Magazine 6.8 SPC Stainless Steel available at CheaperThanDirt (these appear to be manufactured by ASC, they literally look identical to the ASC 6.8 / .224 mags)
PSA D&H 6.8 25RD MAGAZINE GEN 2 25-ST6.8-QPQ-MP-PSA from Palmetto State Armory or SS Arms
ASC AR-15 6.8 SPC / .224 Stainless available in 5, 10, 15 and 25 rd capacities from ASC directly, OpticsPlanet, Gunmagwarehouse etc. (I use these and the build quality is very good through and through)
BARRETT AR-15 30RD MAGAZINE 6.8 SPC available at Brownells or from Barrett directly
Magpul (LWRC specific variants that may not fit in all lowers) SIX-8 polymer magazines available in 5, 10 and 20 rds at LWRC's website or 30 rds at Brownells
Known 6.8 SPC Bolts:
ARP 6.8SPC/Valkyrie 9310 alloy enhanced bolt
ARP 6.8/Valkyrie 9310 Superbolt
LWRC INTERNATIONAL - AR-15 ADVANCED COMBAT BOLT ASSEMBLY 6.8 SPC II/224 VALKYRIE from Brownells or LWRC
JP ENTERPRISES ENHANCED BOLT - 6.8 SPC II available at Raineer or from JP
Stag Arms .224 Valkyrie/6.8 SPC II Bolt - Right Handed
FailZero offers a complete BCG: 6.8 SPC EXO NiB Bolt Carrier Group
Quality 6.8 SPC Barrels
ARP has quite a few variants in 10.5, 12.5, 14.5, 16, 18 and 20 inches in 3R, 5R, 4 in 1:11 and 1:10 with their performance chamber, 4150-CMV nitrided in various profiles and cuts
Daniels Defense 6.8MM, MID-LENGTH, 1:11, S2W Hammer Forged / Chrome Lined 4-grove available in 16 and 18"
WilsonCombat SPC II chamber "Match Grade" 416R Stainless 4-groove 1:11 twist available in 11.3, 14.7, 16 and inches (some variants are fluted)
BisonArmory SPC II Chamber in 416R Stainless 4-groove 1:11 twist available in 16, 18, 20 and 22 inches
SaternBarrels SPC II Chamber in 416R Stainless 4-groove 1:12 twist available in 16, 18 and 20 inches
Anyway, the point is that 6.8 parts are as plentiful as the load choices (weather factory loads or hand loads). There may be others I'm not aware of as well. And there are companies that sell complete mid-range and high end uppers or complete rifles like ARP, WilsonCombat, LWRC / LMT, Daniels Defense, StagArms etc. I don't have any particular issues with 6.8 wild cats, but most people don't re-load and it seems there are plenty of choices for 6.8 mags, barrels and bolts. I'm not seeing a particular advantage of 6.8 wolverine other than the fact that you can use 5.56 mags and bolts.
Last edited by win&legend; 03-11-20 at 09:02.
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