New Caliber - 300 AAC Blackout

[LiquidTension]

I got some trigger time with the cartridge at the silencer shoot. It's definitely on my short list now.

 

[youngsait]

Reasonable priced 300 AAC Blackout

I found a reasonably priced 300 AAC Blackout from

http://www.model1sales.com/index.cfm?fuseaction=category.display&category_id=655

I hope this is not a duplication. They sell 300 Whisper also.

 

[rsilvers]

http://www.model1sales.com/index.cfm?fuseaction=category.display&category_id=656

 

[rsilvers]

 

[rsilvers]

http://www.midwayusa.com/viewProduct/default.aspx?productNumber=680890

Redding dies are out.

 

[Avidtech]

300 AAC Why?

Is there any new technology in this cartridge? If not it has already been done and I cannot see a reason for this cartridge. The ballistics are not there for other than Close Quarters and we have numerous CQ rounds already. Maybe we should get behind the 6.8 spc and force the ammo price down. It works for me.

 

[Mike1234567]

^^^ Not really but, from what I've heard, Remington is doing a far better job of promoting the Blackout than previous attempts by others with effectively the same cartridge.

 

[rust collector]

That's the wonderful thing about 300 AAC. It's so retro. It's like the flight of the bumblebee--shouldn't work, but it does. There is no replacement for displacement, and a big ol' bullet can do a thorough job even if it isn't approaching the speed of light.

No disrespect intended for the 6.8. Jack O'Connor certainly thought highly of it back in the 50's.

 

[Avidtech]

Marketing

Yes, promotion

 

[Avidtech]

For the record we are referring only to AR15 compatible cartridges in this thread. Otherwise we really don't want to waste our time with the 300 AAC. Alexander Arms has a .50 Caliber that will blow the arm off someone, that has been done as well as the grendel.

 

[rsilvers]

Not really new so much as standardized so that it can finally take off.

The concept is that if 90+ % of shootings are within 300 meters, then why design rounds to be optimal at 600 meters?

For example, 5.56mm beats 300 AAC BLACKOUT at 400-600 meters. But 300 AAC BLACKOUT beats 5.56mm from 0 to 200 meters.

If you shoot 0-200 meters 88% of the time, and 400-600 meters 3% of the time, then why compromise the round? If something is that far away, bring in a 308 M110.

30-30 is super popular, and this is close to that, but in an AR with good ergonomics, optics compatible, and where you can hunt with 5 round magazines and later use it for home defense with 30 round magazines.

 

[rust collector]

Actually, the thread title is 300 AAC Blackout. I'm sure there is a thread for the 6.8 spc somewhere...

 

[451 Detonics]

They are no more the same cartridge than 5.56mm is the same as 223.

The data for the 300 AAC BLACKOUT is verified at 55,000 psi or less. The data for the 125 300 Whisper(R) is an unknown pressure - could be 65,000 psi for all we know - and probably is.

Seeing as Hornady is loading 300 Whisper ammo I am sure the ammo is loaded well within SAAMI specs. Why bad mouth them?

Bragging on SAAMI is overblown, every ammunition manufacturer pressure tests it's ammo.

 

[Avidtech]

Ok Rust, 300 AAC discussion

Is it true? Only a barrel change to my AR and I am good to go with the 300 AAC?

For what are most gunners using this round? What game or home defence?

 

[rust collector]

Rsilvers is your resource for all things 300 AAC. I like the idea, but have zero experience with the chambering.

I suspect that reading the rest of the thread may supply some answers, but the attraction for me is the compatibility with a can, and no need to exchange or modify gun parts other than the barrel or upper.

 

[rsilvers]

Seeing as Hornady is loading 300 Whisper ammo I am sure the ammo is loaded well within SAAMI specs. Why bad mouth them?

That comment was in reference to some unknown-origin load data that you cited without reference. Did you mean that was Hornady data? I did not know who it was from.

Bragging on SAAMI is overblown, every ammunition manufacturer pressure tests it's ammo.

Many don't. And many that do, do not do it with professional grade gear.

 

[rsilvers]

Yes, just a barrel change on an AR.

Pretty low prices at some places:

http://www.model1sales.com/index.cfm?fuseaction=category.display&category_id=656

 

[Avidtech]

300 AAC Quick Change

Thanks Silver,

Ok, so just the barrel and my existing mags work, great. That is a little better than the 6.8 change over. I ended up with a whole new AR after buying the 6.8 upper I couldn't resist getting another lower etc.

A quick change barrel setup is looking better and better for my next AR. It would be nice to quickly switch setups.

 

[68wj]

I have always been an advocate of pairing bolts with barrels to ensure headspace and wear-in is maintained (regardless of 5.56 bolt commonality). Are there headspace gauges available for users doing barrel swaps?

I know there is rarely an issue with these types of changes, but I hear a lot of "just swap your barrel and use your same bolt" talk and I guess it's the old armorer in me getting concerned.

 

[rsilvers]

We designed our barrels to correctly headspace with any bolt correctly made to military specs. This is what Colt does also.

Do all AR makers do this? No.

If you change your barrel and bolt you should check it with a gauge set.

http://www.midwayusa.com/viewProduct/?productNumber=643691

http://www.midwayusa.com/viewProduct/?productNumber=196624

 

[NG VI]

So wait, you are saying that the Whisper is an unknown quantity and possibly (you seem to be insinuating it's most likely) loaded to unsafe pressure levels, yet here comes this-

Regarding velocity - 300 Whisper(R) compared to 300 AAC BLACKOUT - if you load both to the same 55,000 psi pressure, the 300 AAC BLACKOUT in a 14.5 inch barrel would be expected to match the 300 Whisper(R) in a 16.1 inch barrel. Or another way to look at it - 300 AAC BLACKOUT in a 16.5 inch barrel would be expected to match a 300 Whisper(R) in an 18 inch barrel.

You think a slightly longer leade would make a lower (insinuated) pressure cartridge with the same case capacity and form develop the same velocities as an identical, higher pressured cartridge out of a longer barrel? How does that work?


Personally if I were to buy one, it would be a 20", it's my favorite barrel length.

 

[Mike1234567]

I have no personal experience with SS but, from all I've read, SS ammunition usually has faster burning powder and less of it due to less availability of space caused by longer bullets. So shorter barrels may actually provide more velocity. Of course, one doesn't want to exceed 1050 FPS or so but the ideal would be to find the right barrel length to allow complete powder burn just before the bullet leaves the muzzle... just as in any rifle... but it's even more important for SS ammo to minimize the possibility of a squib plus eliminate muzzle flash as much as possible. Longer/heavier bullets are desirable for SS... assuming one has fast enough twist rifling... because with lower velocity more weight is needed to be effective.

 

[rsilvers]

You think a slightly longer leade would make a lower (insinuated) pressure cartridge with the same case capacity and form develop the same velocities as an identical, higher pressured cartridge out of a longer barrel? How does that work?

I can't follow you.

I specifically said both were loaded to 55,000 psi and I did not insinuate that one was a lower pressure cartridge.

 

[DoubleTapDrew]

I ignored the .300 whisper and blackout initially, but after reading more about it I'm really starting to want one! Better smack than a 5.56 out to a couple hundred yards, very accurate, very quiet when suppressed, plus I have a boatload of .221 fireball brass from when we shot ground squirrels more often, and an AR lower that's feeling neglected. hmm...

 

[rsilvers]

This one has as 12.5 inch barrel and was shot with 58 proof rounds on the barrel and bolt. Then I shot a 50 yard 5-shot group with Remington Premier Match 125 and the 4x scope.