6.8 Rem SPC

[Paule]

The main reason you see shortish barrels in 6.8 is that velocities don't increase much past 18". Best velocities I have gotten with 16" (consistently) have been around 2600 fps, and 2720 or so in an 18". Same load gains 5 fps in a 20". I have had a few loads that made major in a 20", 2800+ fps, but they were not consistently repeatable, and were done with a powder that is not available in canisters. The newer factory ammo is slower by 50-100 fps too, so making major is problematic. I have only been able to do it safely in a test upper with a strain gauge to measure chamber pressure. It is easy to get loads that are above the limits of the AR bolt head and still see no pressure signs in the case or primer, so handloading hot is not for the faint of heart (donning bulletproof underwear now).

Another solution that you may want to consider is heavier bullets in .223 for longer targets. I started shooting MK262 Mod1 ammo (77gr SMKs at 2950 fps), and they move big flashers with authority. Recoil is noticeable and a steady diet will shoot out a barrel quicker (much quicker). But a few per match for the steel at 250 + will make you smile. Black Hills loads it under contract and sells blemished rounds. They are accurate, 2-2.5" at 300 yards, as long as you have 1-8 twist or faster. Some 1-9s will work, some won't.

[kimel]

Thanks for the additional info Paul. Sounds like 6.8 major is aways off yet and may not be attainable.

I have been shooting 69 gr SMKs and good hits will roll flashers well but marginal hits (which seemed to be most of the hits I got this past weekend) were difficult to call.

I have ordered some 77gr SMKs to load up and play with. I shoot a JP 1 in 8 barrel so no problem with the 77s.

I still may build up a 6.8 upper just to have around and play with. Or I'll build it up as a shorty carbine truck gun. One can never have too many guns.

[Paule]

I neglected an important point on the MK262 ammo. The cases are not standard .223 cases. They are beefed up at the base/lower case walls to handle the higher pressures of this round. Getting 77SMKs to go that fast with standard cases is not recommended. Way too hot.

[davidwiz]

I neglected an important point on the MK262 ammo. The cases are not standard .223 cases. They are beefed up at the base/lower case walls to handle the higher pressures of this round. Getting 77SMKs to go that fast with standard cases is not recommended.  Way too hot.

Is there any place currently selling the MK262? It looks like Gizmo's Guns used to carry it, but doesn't anymore.

[cottyw]

I’d like to reinvigorate this topic. Indulge me with some of the positives of this cartridge:

- Uses Jack O'Connor’s favorite caliber: .277

- Is based on the All American 30/30

- Was invented by a Green Beret

- Kills deer better/ maybe steel

- Finally makes all the WWII, Korean War and Vietnam guys at the VFW shut he F up about the black rifle! (I can drink in peace)

Man, what’s not to like…I’m sold.

Seriously,

If you loaded it with 90gr bullets it wouldn’t be that different than 77grainers for recoil and trajectory. The holes might be big enough to see up close for hoser stages. I looked into it and if I can get 6 reloads out of the brass I can reload it for around $250 a K. The magazines are on sale at midway for $25, brass is ready and the barrels are sold by DPMS and Bushmaster. The dies and all the data are on the official sites. If you combine it with a piston system you might have the next generation 3-gun gun. It really seems like the .40 for rifle cartridges and it’s got big All American appeal. I think I’m going to get behind this even if I look like a guy shooting a .40 cal Glock at an IPSC match back in 1991.

Will

Edited September 26, 2007 by cottyw

[Joe4d]

when this round came out I looked at the specs and thought, gee after all the research and development these guys have invented A medium cartridge firing a 120 gr bullet at around 2500 fps. One that trades some long range ( most troops cant hit at 300 meters anyway) for increased close range energy. A round that will work in existing assault rifle platforms, Gee these geniuses just reinvented the 7.62X39.

[Viggen]

There is still this little thing called Major.

Is it there yet? I haven't heard.

[Derek45]

6.8SCP is VERY Cool.

Grafs, Midway, Aimsurplus, etc sell ammo. Seems like it's everywhere.

When you can buy LEE dies, and get brass at cabela's, I'd say this round is on the map.

It's a fun cartridge, but for 3-Gun, I'm still using 5.56mm.

[jobob]

I'm wondering why they didn't go with a 6.5mm. With the great ballistic coeficient I think that would be the ticket. Anyway, it seems to be an excellent cartridge.

BTW, Joe4d, I don't think this round is anything like the 7.62x39. The 6.8 is better. Flatter shooting, better penetration, better terminal ballistics, works better in the M16/M4 platform (can use the same lowers). AND, it isn't a round that was invented by commies!

[norbs007]

It's a great round, recoil is not at all that harsh. After shooting my 13.7" with a 110gr. bullet, my next build will be a 16" midlength with a Surefire comp and a JP gas block.

[uscbigdawg]

Why 6.8 isn't gonna work (well) in 3-Gun. First, it doesn't make major. Second, so since you're not making major, there is no scoring advantage over 223. Third, the components cost more. Finally, the ballistics, from what I've seen, aren't much better than heavy 223 bullets anyways.

So what does that leave? 6.5 Grendel makes major PF with heavier bullets. The recoil is described as a little harsh since the loads so far that make major are again using the heaver bullets >130 grains. The hot ticket would be making major with the great selection of 123gr. bullets. A lot of European friends are trying but have hit a bit of wall, but we agree that it's due to the smaller powder selections that they have there compared to here. When I return to the US, I'll be working up loads for this, but don't count on running anything smaller than a 20" barrel (maybe an 18").

Probably the biggest factor to not going major PF though in the US (vs. Europe) is our scoring system/stage design. In the US, any target we have over 75/100 yards is usually steel. So, it's 5 points or nothing, major or minor. In Europe, they have paper targets out to 300/400m and so the stage design/construction dictates an advantage to go with a major PF rifle.

What does that leave? There are other calibers that are in the works, that are designed to work within the AR-15 receiver that make major PF. As with any other thing with the AR in 3-Gun though it'll come down to reliability and availability of magazines for the platform. 6.5 for example. Unless you get extensions, you're stuck with 25 round mags. There's no Beta mag for them (not that I would use one) and we have a hard enough time getting AR mags (solved by Magpul, Brownell's & HK).

I picked up a 16" 6.8 upper on a whim. Mostly for plinkin' and probably for the occasional match/class. My thinking is that IPSC may want to consider lowering the major PF a smidge to allow these newer calibers a chance, but then what would the real benefit be? Also, will it kill the 308 (AR10) as an option? Just thinkin' out loud. I have a LR-308 and love it. It needs some tweaks to it to be awesome but figure that if JP has some time to work out the bugs, we can expect an AR platform that will take FAL mags (i.e. large capacity and they WORK!).

Rich

[cottyw]

Good posts guys,

I am seriously considering putting some of this tax free money toward a XCR. It would support all the people supporting 6.8. Will I shoot it in 3-gun, probably not unless it’s more of an IDPA/tactical format.

Will

[uscbigdawg]

cottyw,

Any advantage to using it in a IDPA/tactical format? Just curious. Regardless, when you get back to Bragg, look me up and we'll have to get together and shoot. I'll be trying to rally as many folks as possible for match carpools in NC for those of us in and around Bragg.

Rich

[Joe4d]

BTW, Joe4d, I don't think this round is anything like the 7.62x39. The 6.8 is better. Flatter shooting, better penetration, better terminal ballistics, works better in the M16/M4 platform (can use the same lowers). AND, it isn't a round that was invented by commies!

Flatter shooting ? sightly, but by such a tiny amount as to not matter in fact with equal quality ammo there is no difference. You cant compare ballistics of super premium precision bullets and powder to another round that comes out of a 40 year old sardine can. when you consider it's purpose of a medium to short range cartridge, better terminal balistics ? thats a function of bullet design which isnt caliber specific, granted an equal weight 6.8 will have a higher balistic coeficient than a 7.62 but again if you plug numbers into a calculater the differences again at shorter range are irrelevant, and even uncertain as a case can be made that the larger diameter hole gives it a "terminal advantage" better penetration ? again yeh right the difference is so minor as to be irrelevant, penetration can be effected by bullet design and material and how much penetration do you need to kill cardboard ? or if your shooting live targets probably less is better. About the only advantage I can see is the M16 platform, which isnt much of one because allmost every part in it has to be changed, yes it's easier for us because the lower is the same and thats the "FFL pain in the butt to order part, but manufacturering the gun as a hole the lower isnt that big a deal compared to the barrel and bolt. And besides lableing a round as "Better: because it works in a specific platform is a thought process I disagree with. Change the platform it isnt that great to begin with. A big and I mean huge advantage for 7.62X39 especially for this crowd and our uses is the availability of cheap blasting ammo, and I am sure with brass cased well constructed reloads acuracy can be had as well. It will also make major pf from a 20" tube with published load data,

[cottyw]

I like the round (7.62x39) I just don’t like the platform. I have had to use a lot of them lately for training and self-defense. The problem is the safety. I have even tied a loop on the selector lever but it is hard to get your finger in under stress. Most of my counterparts carry the weapon without a round in the chamber. I have personally treated 3 indigenous soldiers who accidentally shot themselves in the foot, peaking over building walls with their finger on the trigger. I know the AK is a good rifle and have seen it prove its worth in battle. The ergonomics are difficult and I think that’s why it is limited in 3-gun. This type of discussion helps me frame arguments as a professional so when I have a chance to talk to those at the top I can make a cogent argument.

Separate issue: Would the size of the 6.8spc cartridge prevent it from going over the top of the bolt and alleviate that type of catastrophic malfunction? Would an op-rod from a gas piston prevent it with standard .223 cartridge?

[Joe4d]

a round is a round a platform is a platform, two different issues. plenty of designs that would work quite well. or for that matter we could invent a new design. but back to the 6.8 and why it's gonna flop. No surplus source, no significant advantage over current rounds or allready established mid power cartridges. Limited to no government interest.

[cottyw]

Even if the military does not pick it up couldn’t it find a home in the Law Enforcement community? This is how we got 40 S&W which is what most IPSC/USPSA guy’s use.