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Old October 31, 2012, 07:04 AM   #26
Marquezj16
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I need to go to your range and get some brass.
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Old October 31, 2012, 07:23 AM   #27
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bed- I'm curious what pressure those AA2200 loads in your link are working at ...and what level of safety margin they have..... I could run 3200 f/sec .270 WIN loads with 48.5 gr of IMR 4064 .... but that'd wreck cases on a mild day, and guns on a hot one.

The Hornady 120gr SST load almost has enough energy to be a 300 yard deer round .... near perfect fo kids! With a longer barrel ...... maybe on my list.

With the small case capacity, it'd be conducive to using a suppressor, too .... another plus for it. I know it's still supersonic, but I want the can to dampen muzzle blast to make the gun more user friendly, not to make it silent.

The 6.5G was looking really good to me for this, but since I already stock .277 bullets......

The only downside for my purposes is that .277 and .264 suppressors are pretty much a build your own proposition...... a can made for the .308 would work, just not as well.


It's an interesting round, and I may very well get one*..... but there's still no way it is has an effective range of 900 yards......

*Probably a bolt action with a long throat .....
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Old October 31, 2012, 08:25 AM   #28
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A wealth of info and opinions thanks guys. Both cartridges were designed to add umph to a small platform and for that I agree both are great rounds but from a hunting perspective where most shots are going to be 500 yards or less the 6.8 is a flatter shooting more accurate round. I don't want to have to start doping just past 100yards is basically what I'm saying.
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Old October 31, 2012, 08:27 AM   #29
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It all depends on the US military

The origin of the 6.8 was the military and there it hangs in the balance. It is an experimental caliber. If the military adopts it will trive, if it doesn't it will likely slowly wither.

There!!! fixed it. But I do like a good laugh
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Old October 31, 2012, 09:29 AM   #30
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Quote:
The origin of the 6.8 was the military and there it hangs in the balance. It is an experimentary caliber.
I think I have misunderestimated the malleability of the American language....

I doubt it will go away if hunters find it usefull. With the popularity of the AR rifle, and the unsuitability of the .223 round out of carbine length AR's for deer hunting, I see a niche there.....

120 grains at 2450 with a BC of .4 beats the tar outa a thuddy-thuddy for bambi applications..... and a 6.8 upper will cost less han a new levergun, too.
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Old October 31, 2012, 04:41 PM   #31
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jimbob- WRT pressure, you need to know that there are two levels of loads out there, similar to the difference between .223 Remington and 5.56 NATO:

Remington screwed up the cone angle and leade on the print they submitted to SAAMI. AFAIK, only Ruger and Model 1 Sales still use this chamber, but there are still some out there from other companies several years ago, that is the source of the neutered loads that you commonly read about, and most factory ammo is still loaded to work in the SAAMI chamber, including the 120 grains at 2450 load you mentioned.

Most use the spc2 chamber, and that along with a 3-5 groove 1:11-1:12 twist barrel will make all the difference in the velocity you can achieve. Technically, it's not the number of grooves or twist that makes the difference, it's the bore area, and the 6 groove 1:10 barrels were intended for 270 Winchester and have a smaller bore area, the 3-5 groove and slower twist was developed specifically for the 6.8. The proper combination can reduce chamber pressure by over 10K psi, allowing more powder and higher velocity. Handloading is where this cartridge really shines, you could easily get over 2500fps with that same 120gr SST from a 16" barrel and IMO it's too heavy for this cartridge, best efficiency is from 90-110gr. I prefer the 110gr Nosler Accubond for Hunting.

This load was Speer 90gr TNT on 29.4gr of H4198 at 2930 fps from my 16" spc2 5R 1-11.25 barrel. Yes, that is 2 full grains above the max SAAMI load that Hodgdon lists from a 24" test barrel. This brass has been loaded several times already, note the lack of ejector swipes and the primers are round where the firing pin hit:

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Old October 31, 2012, 05:00 PM   #32
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Primers seem to have plenty of radius left .... I am intrigued.....
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Old November 1, 2012, 09:41 AM   #33
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Not specific to the 6.8, but in general, the firearms industry creates the need they seek to satisfy, not unlike an old Baptist preacher...

Every year they (collectively) roll out some new chambering, which everybody has to go out and buy, so then they create ammunition for that chambering, accessories for that firearm, and then, next cycle, repeat.

In the next cycle, all the stuff that was de rigeur in the last cycle finds its way to the unused pile.

Lather, rinse, repeat.

As I see it, the cartridges most likely to remain are those which are, or were, military chamberings, as they will do most jobs adequately, if not excellently, and components are always available. Whether the 6.8 fits in this category remains to be seen. As I understand it, the .mil has had a lukewarm reaction to oddball cartridges, perhaps due to deficiencies in the supply system.

There are exceptions of course, like the 243 and 270, but even these are probably not as popular as they were 30+ years ago, what with the advent of the "new" WSSM or similar chamberings.

YMMV.
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Old November 1, 2012, 09:51 AM   #34
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A buddy of mine has one for deer hunting and loves it. My thoughts are the 6.8 is a good round that has alot of potential for hunting and LE use. The widespread availablity of 5.56 will keep it from becoming the top AR round but it will IMHO outlast most of the other newer AR rounds.
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Old November 1, 2012, 11:21 AM   #35
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I hope the military will get behind the 6.8 catridge and move away from the .223

A couple of years ago I was talking to my son-in-law, who has done two tours of Iraq, and I was showing him my POF 308. He said that he would have loved to have it while in Iraq.

It happened to him that several times, while on patrol, the enemy would pop-up from behind mud walls, the .223 rounds would not penetrate but the AKs rounds (7.62x39) did. After that they assigned M-14s to two squad members.

The 223 was really for jungle fighting not desert fighting. As always our beloved government is way behind the ball.

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Old November 3, 2012, 10:10 AM   #36
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Eppie,

Not likely to happen. The .mil just invested a bunch of money in "barrier blind" ammunition to punch through things like automotive windshields. The Army has M855A1, the USMC Mk318.

Those two M14's were for the Squad Designated Marksmen, who have the job of supporting the squad with precision fires as part of their Rifleman duties.

I don't see that many folks outside of SOCOM using the 6.8, and even then a lot of SOCOM guys are choosing the SOPMOD M4 with 77gr Mk262 Mod1 ammo.

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Old November 3, 2012, 11:39 AM   #37
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Jimro

Yesterday I received my Guns & Ammo issue and one of the articles supports your conclusion.

There is just too much inertia and in the system. We're buying $20 million aircraft that have no opposing air force, but sending out troops with M-4 and M14.
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