Taurus Firearm Forum banner

Looking for a 300 Blackout upper

2873 Views 35 Replies 13 Participants Last post by  Czechbikr
I'm looking for a 16" (or longer) 300 Blackout upper to put on my AR-15. Any recommendations from experienced shooters?
  • Like
Reactions: 2
1 - 20 of 36 Posts
Look at PSA. They often have specials.
  • Like
Reactions: 2
Mine is a Radical Firearms which works well and was on sale.

Attachments

See less See more
2
  • Like
Reactions: 1
Primary Arms is having a pretty big sale right now:

https://www.primaryarms.com/ghost-firearms-16-300blk-elite-bar-upper-gf16e14gfr300bt

https://www.primaryarms.com/CFU16-5-56M4-12FCR_6

I've got a Radical Firearms 10.5" 5.56 upper on my EOTWAWKI AR that I bought from them and it's pretty great.
  • Like
Reactions: 2
radical firearms has a nice selection of barreled uppers in the mid $200's, but I also have some from Palmetto state armory i am happy with but they only go to 16"
  • Like
Reactions: 1
300BLK run on small-ish charges of fast powders. They are done with serious burning by 10” or so. This is why they make good SBRs.
I built a 14.5” barrel with a pinned & welded muzzle brake to reach 16” oal . No paperwork or added $$.

The gun gun is moa at 100 yds and a very good 30 cal CQB/run n gun shooter.

Imho save the 20” barrels for your Creedmore build!! ;)
  • Like
Reactions: 5
this will help you a lot
https://www.ar15.com/forums/ar-15/300BLK-Ballistics-vs-Barrel-length/121-709725/
the chart is down a few posts. after 16" you only get about 20fps/in. changes in velocity/inch drops after 8-10".
so i'd say 16" just to not need paperwork
  • Like
Reactions: 3
Or build a pistol. My current project is a 9" .300 BLK pistol with an 80% lower. Check out DSA for a 16".
If I could find a .450 Bushmaster or .458 SOCOM upper for under $300, I'd be REAL tempted. I really ain't gaining much with a .300 BLK over my SKS for hog busting, but a .45 caliber would whack 'em and stack 'em ...:rofl:
  • Like
Reactions: 3
Here are a couple of very good quality .300BLK uppers from PSA. Only difference I can see is the handguards and free shipping on one. One is $239 plus shipping and the other is $249 with free shipping. Use the BCG and charging handle from your 5.56mm upper.

https://palmettostatearmory.com/psa...ight-m-lok-upper-no-bcg-or-ch-5165448216.html

https://palmettostatearmory.com/psa-16-pistol-length-300-aac-bo-1-8-nitride-13-5-m-lok-fre.html


If I had either one I would immediately swap out the gas block for an adjustable gas block. My 16" .300BLK has carbine gas length and I only shoot supers through it, but I still have the gas turned down some with an adjustable block. The Pistol length will give you the ability to shoot both supers and subs, but that short gas length makes it pretty harsh with hot super loads. Non-Suppressed Subs will be all the way open and probably still struggle to get enough gas to cycle with any sub load under 205 grains.

BTE has a very good adjustable low profile gas block for $35 delivered, https://www.bte-usa.com/bte-set-screw-micro-gas-blocks

BTW, do not get an adjustable gas block that adjusts from the front, once you get a suppressor you will have to remove the suppressor to adjust the gas block and you will need to adjust the gas block with a suppressor.
See less See more
  • Like
Reactions: 2
If I could find a .450 Bushmaster or .458 SOCOM upper for under $300, I'd be REAL tempted. I really ain't gaining much with a .300 BLK over my SKS for hog busting, but a .45 caliber would whack 'em and stack 'em ...:rofl:
You and me both...Prices have dropped big time on AR 5.56 and somewhat on 300 BLK but the .458 SOCOM still remains high. Must be supply and demand.
  • Like
Reactions: 2
just a suggestion to try it out with the standard gas block. both my 16 and 8" .300's(both from PSA as nitrided complete uppers with BCG) shoot fine with both super and subsonic factory loads . you may find you are OK with it stock. also if you start swapping things out right out of the box, the seller may wash his hands if you have issues. oh, and i am sold on nitrided barrels. the ease of cleaning and lack of copper fouling is amazing
If you supress, i defer to the experts. i have just begun to learn all the things that may need tweeked so for me it's ear plugs for now

Here are a couple of very good quality .300BLK uppers from PSA. Only difference I can see is the handguards and free shipping on one. One is $239 plus shipping and the other is $249 with free shipping. Use the BCG and charging handle from your 5.56mm upper.

https://palmettostatearmory.com/psa...ight-m-lok-upper-no-bcg-or-ch-5165448216.html

https://palmettostatearmory.com/psa-16-pistol-length-300-aac-bo-1-8-nitride-13-5-m-lok-fre.html


If I had either one I would immediately swap out the gas block for an adjustable gas block. My 16" .300BLK has carbine gas length and I only shoot supers through it, but I still have the gas turned down some with an adjustable block. The Pistol length will give you the ability to shoot both supers and subs, but that short gas length makes it pretty harsh with hot super loads. Non-Suppressed Subs will be all the way open and probably still struggle to get enough gas to cycle with any sub load under 205 grains.

BTE has a very good adjustable low profile gas block for $35 delivered, https://www.bte-usa.com/bte-set-screw-micro-gas-blocks

BTW, do not get an adjustable gas block that adjusts from the front, once you get a suppressor you will have to remove the suppressor to adjust the gas block and you will need to adjust the gas block with a suppressor.
You can reload 300BLK for less than .223 if you shoot Hi-Tek lead bullets.

I built both of my 300BLK uppers using Anderson and Bear Creek uppers and two different barrel brands, but both are pistols. I do not see the need for a 16" barrel, especially seeing as how a pistol length gas system may be needed for reliable cycling - depending on what you plan to shoot with it. If you're looking at velocity, then the gains just really aren't there as they are with true rifle cartridges, as (many have already said) the 300BLK was designed around a shorter barrel and geared to suppression first and foremost.

Both PSA (Palmetto State Armory) and Primary Arms have decent uppers - the PSA uppers are built "in house" and PA just resells but I've heard only good things about the Ghost brand (Radical is somewhat hit or miss...) and all of these run pistol length gas systems.

Why do you want the long barrel? What is your goal with this gun? What do you intend to shoot (load-wise)? Do you intend to suppress? To you plan on reloading for it?

If you just like the look of a 16" 300BLK, then by all means, pick one of the PSA or PA articles mentioned above and either run your existing BCG and CH, or purchase them along side. Can't really go wrong.
See less See more
  • Like
Reactions: 1
yeah, it's those darn laws about barrel length. after 8 or 9" the velocity gains start to drop and 16" seems to be about the longest that makes sense, because of the law. certainly doesn't make sense to buy a shorter barrel then weld some tactikool piece of pipe off it just to make 16". Other than the velocity gain, as long as i am shooting off a rest i don't see any accuracy difference between the 8 and 16" barrel. but it i was hunting deer, i'd probably want the velocity of the 16" to extend my range that extra 50 or 75 yards for reliable expansion
You can reload 300BLK for less than .223 if you shoot Hi-Tek lead bullets.

I built both of my 300BLK uppers using Anderson and Bear Creek uppers and two different barrel brands, but both are pistols. I do not see the need for a 16" barrel, especially seeing as how a pistol length gas system may be needed for reliable cycling - depending on what you plan to shoot with it. If you're looking at velocity, then the gains just really aren't there as they are with true rifle cartridges, as (many have already said) the 300BLK was designed around a shorter barrel and geared to suppression first and foremost.

Both PSA (Palmetto State Armory) and Primary Arms have decent uppers - the PSA uppers are built "in house" and PA just resells but I've heard only good things about the Ghost brand (Radical is somewhat hit or miss...) and all of these run pistol length gas systems.

Why do you want the long barrel? What is your goal with this gun? What do you intend to shoot (load-wise)? Do you intend to suppress? To you plan on reloading for it?

If you just like the look of a 16" 300BLK, then by all means, pick one of the PSA or PA articles mentioned above and either run your existing BCG and CH, or purchase them along side. Can't really go wrong.
I ain't jumping the hoops to get a short barrel OR a silencer, personally.
  • Like
Reactions: 1
spoke with a guy at my local club who got hooked up with the wrong silencer manufacturer for a .30 caliber one and he was stuck waiting well over a year for paperwork after he had paid for everything due to the business waiting till he had a big enough batch on order to initiate paperwork. then he was out $1400 for the darn thing with the fees and if he wants a stupid little adapter to use it on an AR barrel it's another $100. in the movies a pillow works just fine and Kohles had them on sale for $3.99 last week.
I ain't jumping the hoops to get a short barrel OR a silencer, personally.
  • Like
Reactions: 1
Bear Creek Arsenal makes complete uppers with BCG/CH in 450 for around $350
Bear Creek Arsenal makes complete uppers with BCG/CH in 450 for around $350
EXCELLENT! Thanks! I book marked it. They also show 7.62x39 uppers, but folks have told me they don't work well with a .223 lower and straight mags.

https://www.bearcreekarsenal.com/upper-assemblies/ua450chb16124-p-12-mlok
  • Like
Reactions: 1
By all means test out the fit, form, function of your new upper before replacing any parts.

But....the adjustable gas block will smooth out the cycling of the action with supers, and it will last longer, work longer, and cycle better. BTE ships instructions on how to adjust the gas block with their product. Essentially, you are adjusting the system from too much gas, to just enough to comfortably cycle the action. Remember, a pistol length gas port is using higher pressures, higher heat gas streams to operate the action when shooting supers. Pistol length gas ports are designed for the use of subsonic loads, where there is little gas pressure to cycle the action. A pistol length gas port on a .300BLK may have a port hole as large as .125" to accommodate sub loads and while that is great, it is also a lot of gas to dump into your action with a super load.
See less See more
  • Like
Reactions: 1
EXCELLENT! Thanks! I book marked it. They also show 7.62x39 uppers, but folks have told me they don't work well with a .223 lower and straight mags.

https://www.bearcreekarsenal.com/upper-assemblies/ua450chb16124-p-12-mlok
I have a 7.62X39 upper on a standard 556 lower. I had to buy an actual 7.62 mag designed for the AR platform to get reliable feeding.

Gun Firearm Assault rifle Rifle Machine gun
See less See more
  • Like
Reactions: 2
1 - 20 of 36 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top