300 aac blackout

[krob]

has anyone here built an ar chambered for 300 blackout? thinking of building an upper to go with my rock river lower was thinking of a 12.5 inch barrel and supressing it pros, cons, ideas?

thanks
rob

 

[BradMacc82]

Yep.

Done a few now.

16" Noveske barrel, very accurate.

View attachment 87645

 

[BradMacc82]

And a 12.2" Noveske barrel, starting life as a pistol, going to end up a SBR.


View attachment 87646

 

[BradMacc82]

Pro's -

*30 cal projectile in a 5.56 package.
*Only dedicated 300BLK part needed, the barrel.
*When suppressed, very quiet on subsonic ammo.
*Can be used for deer in MD, provided your using supersonic ammo.

Con's -

*Limited range, subsonics are good for 250 yards and in.
*Factory loaded ammo is in short supply currently.
*Noveske barrels ain't cheap, and not always available in desired length.

 

[IndispensableDestiny]

I'll finish mine if I ever get the barrel back from the gunsmith. It needed the flash suppressor pinned and welded. The barrel is a Noveske.

Today I snatched 500 Hornady .30 cal 110 grain spire point bullets. That will be for my blasting ammo. I'm not interested in subsonic.

 

[alpine44]

The 300 Blackout is an excellent caliber that only requires a barrel change in an AR15.

You can use "real" hunting bullets and have the confidence of shooting a heavier bullet (typically twice as heavy as a 5.56x45) on game.

The cartridge also excells in short barrels. 8-9" barrels are long enough to burn the powder completely and deliver great performance without excessive muzzle blast and flash. A 16" barrel will only yield ~150 ft/sec more muzzle velocity than a 9" barrel.

Lastly, you can cast your own cheap lead bullets for this caliber. If you do not go crazy with the powder charge you may even get away without a gascheck.

The brass can be formed from 5.56x45 casings. There is a guy on gunbroker who converts 1000 5.5x45 cases to 300 BLK and removes the primer crimp for ~$70.

On the downside, factory ammo is expensive, hard to find and in my experience not nearly as accurate as the hand rolled loads. In order to take full advantage of the 300 BLK you should reload, IMO.

 

[Sticky]

Good info! It's on my list of 2 to build... soon... lol

I do reload, so that is no problem

 

[krob]

thanks for the info.....brad how long is the hand guard on the 12.2 barrel? i plan on reloading so i should be good on ammo at some point. i ordered a lower receiver should be in some time next week planning on keeping that for a later build.

 

[BradMacc82]

Both run a full rifle length Yankee Hill rail.

 

[HT4]

The cartridge also excells in short barrels. 8-9" barrels are long enough to burn the powder completely and deliver great performance without excessive muzzle blast and flash. A 16" barrel will only yield ~150 ft/sec more muzzle velocity than a 9" barrel.

This.

I'm curious why the OP is looking at a 12.5"...

 

[BradMacc82]

This.

I'm curious why the OP is looking at a 12.5"...

Guessing because it's a good medium between 16" velocity, and compact size of 8"/10"???

 

[krob]

im planning on supressing it and with a 16 inch barrel im figuring 23 24 inches? also i dont see much velocity loss with a shorter barrel dont plan on shooting past 200 yards with it

 

[Les Gawlik]

Has anyone tried the cleaned brass sold on Gunbroker? Some sell the primed case and Hornaday projectiles.

What equipment would you recommend to measure the powder and seat the bullet? What sort of powders are recommended, or to be avoided? If the primers are no seated, are these small or large rifle primers?

 

[Biggfoot44]

( Insert the entire discussion regards Handloading. )

Yes , those take SmRifle primers.

 

[r3t1awr3yd]

Has anyone tried the cleaned brass sold on Gunbroker? Some sell the primed case and Hornaday projectiles.

What equipment would you recommend to measure the powder and seat the bullet? What sort of powders are recommended, or to be avoided? If the primers are no seated, are these small or large rifle primers?

A scale.
A press.
Smokeless recommended, black powder to be avoided.
Small rifle.


lol

 

[bangbangbye]

Nice post. Here is my build. Waiting on a few tax stamps to SBR and suppress. Wilson combat barrel on mine. Yes, that is an 80% lower that looks like a seekins..

The 300 Blackout is an excellent caliber that only requires a barrel change in an AR15.

You can use "real" hunting bullets and have the confidence of shooting a heavier bullet (typically twice as heavy as a 5.56x45) on game.

The cartridge also excells in short barrels. 8-9" barrels are long enough to burn the powder completely and deliver great performance without excessive muzzle blast and flash. A 16" barrel will only yield ~150 ft/sec more muzzle velocity than a 9" barrel.

Lastly, you can cast your own cheap lead bullets for this caliber. If you do not go crazy with the powder charge you may even get away without a gascheck.

The brass can be formed from 5.56x45 casings. There is a guy on gunbroker who converts 1000 5.5x45 cases to 300 BLK and removes the primer crimp for ~$70.

On the downside, factory ammo is expensive, hard to find and in my experience not nearly as accurate as the hand rolled loads. In order to take full advantage of the 300 BLK you should reload, IMO.

 

[IndispensableDestiny]

I finished mine tonight. The optics are temporary, I need to test my loads. I had a Leupold 1-4x20 on a Marlin 1894 and borrowed it for this. I need to use a riser for eye alignment and relief. I'll get higher rings later.

 

[midcountyg]

An old thread, from before the AAC craze
http://www.mdshooters.com/showthread.php?t=58923

 

[Ronin9]

I've considered just ordering a completed upper in 300BLK... but actually came across a Daniel Defense DDM4 V7 in 300BLK for a good price (least I think so). Am now debating on getting the full rig now then another upper in 5.56 at a later date or sticking with my original plan. I've already got a RRA HBAR in 5.56 that I use mostly as a range gun... but am really considering this DDM4 in 300BLK. thoughts from the peanut gallery?