.300 Blackout barrel selection

Skunk

Amongst the Enemy
Full Member
Minuteman
Nov 24, 2003
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Lost in the Sauce
Alright guys, I'm interested in putting together a .300 Blackout. I've got an AR that's been standing in the corner, unfired for three years. I wanna try something different. So, I've been looking at barrels and see there are plenty of choices.

My questions:

1) If I choose a 16" barrel, and I only intend to shoot subsonic ammo with a suppressor, where does the gas port need to be (pistol or carbine location)?

2) If I later shorten said barrel to 12" (after having gotten the SBR tax stamp) will it still cycle if the gas port is for a carbine?

3) What configurations are working for you guys?
 
Re: .300 Blackout barrel selection

If you're running subs, regardless of barrel length, you'll be running a pistol length gas system. I'm running a Noveske 10.2, which includes the low profile gas block, gas tube and pins. I think you'll find that most, if not all, .300BLK barrels are running pistol length gas ports. If you're going custom, I would run this length. You'll be set down the road if you go SBR. This round is a lot of fun in the SBR configuration but I think it's also a great round in a full carbine length set up for supersonic rounds. Great deer gun.

Contact the major barrel manufacturers to confirm. The Noveske's run high dollar wise. AACs are up there as well. Houston Armory has a nice "Pig" stainless barrel (SBR) at the same price. Push the price down with a CMMG, Palmetto State Armory, or model 1 sales barrel to name a few. Enjoy!
 
Re: .300 Blackout barrel selection

I run Noveske 10.2" barrel with pistol gas tube that came with the barrel. I like the barrel set up a lot and it's cycle/locked up well with all the ammo ( factory Remington 115 and 220 gr, hand loaded 150, 220 and 208 gr).
 
Re: .300 Blackout barrel selection

get pistol if at all possible, I have a satern with carbine length and it took lots of fiddling to get even close to working as it should. I forgot to ask when I ordered, just assumed that it would come as pistol length. I finally have it running but in the future would absolutely make sure to get pistol length.
 
Re: .300 Blackout barrel selection

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: BusterB</div><div class="ubbcode-body">get pistol if at all possible, I have a satern with carbine length and it took lots of fiddling to get even close to working as it should. I forgot to ask when I ordered, just assumed that it would come as pistol length. I finally have it running but in the future would absolutely make sure to get pistol length. </div></div>

16 inch barrels work fine with subsonic and supersonic and carbine gas. If yours did not, the most likely cause was that the gas port size was too small - but that can and does happen on any barrel length.

But as was said, pistol length does allow you to cut the barrel down later.
 
Re: .300 Blackout barrel selection

AKA-Spook is building me a 16 inch 300 Whisper with carbine gas for shooting nothing by supersonics. Most likely I will be shooting 125 Matchkings and Ballistic Tips on top of N-110.

He also built me a 20 inch 300 Whisper tailored for 155-175 gn matchkings for some of the different gun games. It is an absolute hammer and runs like a champ.

If I was building one for subs and supersonic ammo, I would go with pistol length gas and an 8 twist.
 
Re: .300 Blackout barrel selection

I am sure you know this but just pointing it out for the record for the benefit of others - it is only 300 Whisper(R) if it was made by or licensed by SSK Industries. It is important to respect SSK's trademark.
 
Re: .300 Blackout barrel selection

OK, it might be me but I just dont see the benefit of the 300 Blackout with supersonic ammo. Subsonic in a working semi-auto platform IS a great idea because its almost totally silent. But once there is a supersonic crack its no different than a suppressed .308 except its ballisticly inferior to a 308. Am I wrong here???
 
Re: .300 Blackout barrel selection

You're wrong...if you look at the weight of the platform the .300 is sitting in...and weight is a concern. A bone stock AR-10, firing .308 win, is in the 9-10 range...easily, before optics etc. The .300 will operate in a 6.5lb AR-15 platform while giving you ballistics on par with the M48 7.62x39 round without the magazine/feed issues that round has historically presented in the AR platform (although it's much better now). A great lightweight deer gun or SD gun with more energy on target than a .223/556. The blackout gives you a supersonic/subsonic option in a lightweight rifle with improved ballistics. Yes, you can get great, and reload fantastic, .308 win subsonic loads...but they won't operate in your semi-automatic firearm. My 2 cents.
 
Re: .300 Blackout barrel selection

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: rsilvers</div><div class="ubbcode-body">

16 inch barrels work fine with subsonic and supersonic and carbine gas. If yours did not, the most likely cause was that the gas port size was too small - but that can and does happen on any barrel length.

But as was said, pistol length does allow you to cut the barrel down later.</div></div>

I have barrels with both, I did have to open up the gas port, and the gun does run, however the pistol length does run much better. Again just with my experience don't waste time with carbine length.

a 400 pound homely woman will work, but I would rather have an athletic 120 pounder that works every time and makes sure you go boom!