New Caliber - 300 AAC Blackout

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I don't think people should stick to the .30 cal, The 6.8 rem SPC is much better ballistically than the 7.62x39 round, and this one is basically no different than that.

I personally think the 6.8 rem SPC will be the main AR rifle caliber in the next 10 years. They fit into a standard AR15 mag as well, and you can already get them with a simple change in your AR-15 upper, in direct impingement or pistol driven configurations.
 
Jath said:
I personally think the 6.8 rem SPC will be the main AR rifle caliber in the next 10 years. They fit into a standard AR15 mag as well, and you can already get them with a simple change in your AR-15 upper, in direct impingement or pistol driven configurations.
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What a wonderful pipe dream. :evil: I cannot see the .223 being replaced at the top unless the military ever drops it (which I also don't foresee anytime soon). The 6.8 should continue to gain ground in the hunting and LE communities (similar to the .40S&W's rise w/o military support).

However, America loves a .30 cal and there is no reason that this cannot also be successful too.
 
40 S&W rose because the FBI adopted it.
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Eh... the FBI also adopted 10mm auto a few years earlier, and many agencies have more recently adopted 357 SIG and .45 GAP, yet none of those are anywhere near as popular. I think the .40 S&W became popular mostly from fitting a need very well - greater performance in a 9mm sized pistol - and some luck.
 
Z-Michigan said:
I think the .40 S&W became popular mostly from fitting a need very well - greater performance in a 9mm sized pistol
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I've wondered why 357 SIG didn't get more popular for this very reason.
 
357 Sig - I assume because 40 S&W was already established and it did not have enough of an advantage.

Also, it never made 357 Magnum performance numbers just like 45 GAP does not make 45 ACP numbers.
 
rsilvers said:
Yes, but they did not adopt the 6.8 yet.
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I did not claim they did, or will. My comment was also not meant inject further 6.8 discussion into this thread. I was simply stating, in response to the previous post, that the 6.8 will continue to develop, and that the .300 can too. The comment about .40 was an observation of a parallel between the success of a pistol cartridge without military support, and a rifle cartridge. My apologies to the forum, please disregard.
 
rsilvers said: "In subsonic mode, it is quiet like an MP5-SD, and yet can shoot through cover (including a utility pole). I don't think so. Our utility poles are like trees, and you want us to believe that in subsonic mode it will shoot through them? Nothing you stated has shown a true subsonic cartridge. Everything has been at least 1100 fps. Unless I am very wrong supersonic begins around 950 fps.
ll
 
rsilvers said: "In subsonic mode, it is quiet like an MP5-SD, and yet can shoot through cover (including a utility pole). I don't think so. Our utility poles are like trees, and you want us to believe that in subsonic mode it will shoot through them? Nothing you stated has shown a true subsonic cartridge. Everything has been at least 1100 fps. Unless I am very wrong supersonic begins around 950 fps.
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You are very wrong. Depending on pressure (=altitude and temperature) the speed of sound is around 1125 fps. 9mm 147gr ammo at 990fps is intended for subsonic use, FWIW.

http://www.aerospaceweb.org/question/atmosphere/q0112.shtml

As for penetrating a utility pole, I haven't seen any testing but I doubt he would claim something like that if it weren't true. A 220gr .308 bullet has serious sectional density, and penetration of both wood and sand is often better at lower impact velocities, not higher. You might find this interesting:

http://www.garrettcartridges.com/penetration.html
 
Robert, when I click your link it says I'm not authorized to read that forum.

ETA: After checking out ST it looks like what you were linking to may have been moved over to 300blktalk.com?
 
you can have a subsonic round be right at the speed of sound at the muzzle, but it drops off fast enough that it's below the speed of sound after a certain distance anyway, eliminating the super sonic crack. 1100 fps is just fine for a sub sonic round.

I think the fact that the .357 sig will work with a drop in conversion barrel on a .40, it will gain plenty of popularity eventually. But people have to ask for it.

the 6.8 is widely adopted by SWAT teams and police throughout the country. It's a superior round to both the 5.56 and the 7.62x39mm rounds. it's more accurate than both, and hits harder than both, while being shot out of the same platform.
 
the 6.8 is widely adopted by SWAT teams and police throughout the country.
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If you have information on which LE Agencies have adopted 6.8 SPC I'd be interested to see it for my own enlightenment.
It's a superior round to both the 5.56 and the 7.62x39mm rounds. it's more accurate than both, and hits harder than both, while being shot out of the same platform.
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How is 6.8 SPC more accurate out the same platform? I really want to see some data on this. Considering that the 7.62x39 case is the parent of the PPC cases.
 
Ok, ok, I know I'm about to make a no no by posting data from Wikipedia, but they are sourced there and it makes sense to me. Plus based on what I've seen on tests with them on shows like deadliest warrior, I am a believer in this round.

Wikipedia: 6.8 rem SPC
The 6.8mm SPC cartridge was designed to address the deficiencies of the terminal performance of the 5.56x45mm NATO cartridge currently in service with the U.S. Armed Forces.[6] The cartridge was the result of the Enhanced Rifle Cartridge program. Participating in the program were U.S. Special Operations soldiers, as well as armorers and other technicians from the United States Army Marksmanship Unit.[7] The development of this cartridge is unusual and interesting in that it was designed by actual shooters in the armed forces, instead of by industry professionals. The goal was to create a cartridge that would bridge the gap between 5.56mm and 7.62x51mm NATO.
The program started the design by using a .30 Remington case, which was modified in length to fit into magazines that would be accommodated by the magazine wells of the M16 family of rifles and carbines that are currently in service with the U.S. Armed Forces.[8]
In tests, it was determined that a 6.5mm projectile had the best accuracy, but a 7mm projectile had the best terminal performance. Further tests showed that a 6.8mm projectile was the best compromise between the two, providing accuracy, reliability and terminal performance up to 500 meters. The combination of the cartridge case, powder load, and projectile easily outperformed the 7.62x39mm Soviet cartridge, with the new cartridge proving to be about 200 ft/s (61 m/s) faster.[9] The resulting cartridge was named the 6.8 Remington Special Purpose Cartridge due to the size of its projectile and the fact that it was based on the .30 Remington case.
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go Here for the full wikipedia article.
 
This is also a good info page - although it doesn't really make any direct conclusions in the comparison between the calibers.

I can't find any lists of agencies employing the round, but I know for certain that many spec ops teams use it, as well as multiple swat teams.

here's an article on it

http://www.tactical-life.com/online/guns-and-weapons/stag-arms-68mm-spc/

If you just go do some of your own research on your own, you'll see that pretty much everyone agrees that it has advantages over both 5.56 and 7.62x39. It's a great hunting round, and a great combat round. It will replace the 5.56 entirely in 10-25 years in the military, in my opinion.
 
Jath, first you said widely adopted. Your only citation is a Wikipedia article that only lists LAPD SWAT based on a show on the Discovery Channel. You're thus far unable to back up your accuracy claims. You say that 6.8 SPC hit's harder than 5.56 NATO, and 7.62x39. SSA has the hottest 6.8 SPC I can find, and that makes 1655 ft lbs. CorBon has a 7.62x39 hunter load that makes 1762 ft lbs. Some of the hottest 5.56 NATO is MK262 Mod 1 and that makes 1295 ft lbs. So, yes, the 6.8 SPC is hotter than 5.56 NATO, but it's not hotter than 7.62x39. 6.8 SPC is also hotter than the 1360 ft lbs that 125gr .300 BLK makes.

The problems is 6.8 SPC does not fit standard AR mags, and does not use standard 5.56 NATO AR bolts & barrel extensions like .300 BLK does. 6.8 SPC wasn't intended as a dual role supersonic light bullet / subsonic suppressed heavy bullet round. .300 BLK lets the end user utilize readily available HPT/MPI 5.56 bolts, and a wide variety of premium 5.56 NATO magazines. Brass for 6.8 SPC is also not widely available, and can't be made from existing brass. .300 BLK can be made from 5.56 / .223 brass.

If you want to go to non standard bolts & mags Alexander Arms has recently dropped their trademark on 6.5 Grendel, so it's no longer proprietary. Brass can be made from readily available 7.62x39 cases. It makes equal energy numbers to the 6.8 SPC at the muzzle, but it can use the higher BC 6.5mm bullets for longer range.

Again, if this can be refuted I'm always happy to learn. My energy numbers are from SSA, Hornady, Remington, and CorBon websites.
 
If you want to go to non standard bolts & mags Alexander Arms has recently dropped their trademark on 6.5 Grendel, so it's no longer proprietary. Brass can be made from readily available 7.62x39 cases. It makes equal energy numbers to the 6.8 SPC at the muzzle, but it can use the higher BC 6.5mm bullets for longer range.

Again, if this can be refuted I'm always happy to learn. My energy numbers are from SSA, Hornady, Remington, and CorBon websites.
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The 6.5 Grendel is known to have feeding issues due to the sharp case neck angle in addition to the other cons already mentioned for the 6.8. The 6.8 magazine bolt issue really isn't one IMO. CMT, LMT, and other big names already make bolts and the magazine issue is trivial.

Isn't the 300BLK also having magazine issues?
 
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I have been using standard AR mags for 30 years with my Whisper...magazines have never been an issue. I f they won't work with the Whisper they normally have problems with .223 as well.
 
ugaarguy said:
Again, if this can be refuted I'm always happy to learn. My energy numbers are from SSA, Hornady, Remington, and CorBon websites.
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Pretty fair assessment. I would clarify the 6.8 uses the same barrel extension, but yes, the bolt is different (moot point unless you are buying barrel blanks). I have never considered this an issue as I like by bolts to be matched to my barrels anyway.

CorBon makes some good, fast ammo, and that 7.62 load is well regarded with hunters. I also will not debate that the 7.62, in a good platform, with quality ammo, is capable of great accuracy. I personally prefer the 6.8 over it in my AR, but wouldn't feel outclassed if I had the 7.62.

One point that often gets overlooked when dealing with hunting bullets (which the 6.8 is primarily being accepting as) is not merely energy, but velocity. For a game animal, a bullet must have enough speed to expand reliably while also having the energy to cause the damage. Without expansion, a game animal will probably still die from the wound, but become coyote scat shortly after. I know this is an area where the .300 etc. is improving thanks to partnerships within the shooting industry. I even expect a photo of Barnes' (Freedom Group) new .300 BO offering to be posted in this thread shortly.
 
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