300 AAC Blackout

[bellavite1]

As I suspect many of us, I am intrigued at the idea of shooting a 30 cal bullet out of an AR.
I do have a few questions, however, that somebody hopefully can answer:

I do realize that a 300 BLK is not a 308, but what is the feasability of using it as a medium range cartridge (say 500yds)?

What kind of accuracy can be expected in this application?
I can tipically hold 1/3 MOA a 100 yds with my 308, sometimes out to 300 yds.

Using a medium weight bullet, say around 150gr, what kind of velocity can be expected from a 20" barrel?

Does a 20" barrel in this caliber even exist?

Yes, I know it is a round supposed to be for CQB, but it would be nice to be able to convert my 20" .556 and have a lightweight med range precision weapon...

Any imput?

[20X11]

As I suspect many of us, I am intrigued at the idea of shooting a 30 cal bullet out of an AR.
I do have a few questions, however, that somebody hopefully can answer:

I do realize that a 300 BLK is not a 308, but what is the feasability of using it as a medium range cartridge (say 500yds)?

What kind of accuracy can be expected in this application?
I can tipically hold 1/3 MOA a 100 yds with my 308, sometimes out to 300 yds.

Using a medium weight bullet, say around 150gr, what kind of velocity can be expected from a 20" barrel?

Does a 20" barrel in this caliber even exist?

Yes, I know it is a round supposed to be for CQB, but it would be nice to be able to convert my 20" .556 and have a lightweight med range precision weapon...

Any imput?

1. Max effective range according to US Gov is 440 yds...can shoot further, but bullet trajectory is a BITCH.
2. Very accurate round...but accuracy will suffer some due to shorter barrel lengths
3. Longest barrel I have seen/heard of is 16"...custom could go longer, but generally not recommended.
4. You can push 125 gr bullet to around 2300 fps...130 gr to around 2200 fps..150 gr to near 2100 fps from a 16 inch barrel...due to powders used for this round a longer barrel isn't going to give much more velocity.
5. Converting a 20" can be done, but you probably will need to swap in a carbine buffer, spring, and spacer (if you have a standard rifle tube on you lower)

[XC700116]

I built mine with an 18" barrel and it works pretty damn well. But since I have it set up with only a red dot on it right now, I wouldn't even bother to try 500. It's quite accurate, easily sub MOA, but not a long range round because of the velocity.

Here's the barrel I used http://www.precisionreflex.com/Detai...99636&CAT=4293 but it's been on BO for months now.

[nisils14]

This video pretty much sums it up about 300blk. 300blk in super sonic is just about completely burned at about 16". Anything longer than that would only net minimal velocity/energy gains and more weight.

[20X11]

As I suspect many of us, I am intrigued at the idea of shooting a 30 cal bullet out of an AR.
I do have a few questions, however, that somebody hopefully can answer:

I do realize that a 300 BLK is not a 308, but what is the feasability of using it as a medium range cartridge (say 500yds)?

What kind of accuracy can be expected in this application?
I can tipically hold 1/3 MOA a 100 yds with my 308, sometimes out to 300 yds.

Using a medium weight bullet, say around 150gr, what kind of velocity can be expected from a 20" barrel?

Does a 20" barrel in this caliber even exist?

Yes, I know it is a round supposed to be for CQB, but it would be nice to be able to convert my 20" .556 and have a lightweight med range precision weapon...

Any imput?

Here is a link to some data posted by the Lead Engineer for the 300 BLK project for AAC...
http://www.300blktalk.com/forum/view...?f=128&t=78987