300 Blackout or 556/223?

[someguy2800]

I like supersonic 300 blackout a lot because it produces a recoil impulse very similar to 223, but with a lot softer muzzle blast, and is a better performer in a short barrel. My home defense/3 gun rifle is a 13.75" 8 twist 300 blackout with carbine gas and a krinkov brake pinned and welded to 16". Very handy rifle and still produces 2400 fps with a 110 vmax out of a very compact package. I have shot it indoors and it doesn't pound on your ears like a 16" 223 does, and a 110gr v max at 2400 is very terminally effective.

I like 7.62x39 in an AR a lot too but I can shoot the 300 blackout a lot faster than a 7.62x39 because the 300 blk has quite a bit softer of a recoil impulse to me. The 7.62x39 wins out in power for hunting, but I think 300 blackout is a better defensive cartridge because it has such a soft recoil impulse and is probably more reliable feeding in 30 round mags.

I have played a little bit with subsonic 300 blackout but it really doesn't do much for me. Considering the cost of good subsonic expanding .308 bullets I prefer to just shoot 147 gr 9mm suppressed.

 

[BreechFace]

IMO unless you want to shoot suppressed the 300 BO does nothing for me. In fact, I don't see where any of the other cartridges that you can fit into an AR-15 platform offer enough advantage over 5.56/223 to be worth the trouble.

With an 8 twist barrel you can shoot pretty much any bullet from 50-80 gr. When you get to 75 gr and heavier 223 bullets they do about about anything you can do with the larger caliber AR-15 choices. The 6.5 Grendel is the only one that remotely interests me.

To have any real gains in performance you have to move to the AR-10 platform.

What about the following, in an AR15? Still not enough difference over the 5.56?

250gr at 2,200fps

Or

180gr at 2,550fps

 

[Ks5shooter]

With cureent bullet selection the 5.56/.223 can do most anything the 300 blk can.I own both though for the fun factor.

 

[Ed]

300Blackout subs take a tiny amount of powder. A Lb will last a long time. I’m not just blasting away with anything these days. I have both but sure do enjoy 300 subs.

 

[Anchorite]

With cureent bullet selection the 5.56/.223 can do most anything the 300 blk can.I own both though for the fun factor.

Exactly. The 223 can do 99% of what the 300Blk can.

 

[KnightHawk]

I have a couple 223 AR Rifles and have considered the 300, but have rejected the idea for the 7.62x39 as a better choice. I’m not interested in a having can.
Others I have considered are the 6x45 and the 25-45 Sharps.
I’m really not into AR’s although I’m warming up a little. I’m a lever and bolt gun guy so forgive me if you find me short sighted.

 

[mcb]

I have ARs in five different cartridges and the ones in 223/556 only get used for gun games. For all the other uses I use my AR's for they are chambered in a cartridge other than 223/556 and 300 BO is my favorite, especially as a subsonic "pistol" configuration. Variety is the spice of life.

 

[earlthegoat2]

IMO unless you want to shoot suppressed the 300 BO does nothing for me. In fact, I don't see where any of the other cartridges that you can fit into an AR-15 platform offer enough advantage over 5.56/223 to be worth the trouble.

With an 8 twist barrel you can shoot pretty much any bullet from 50-80 gr. When you get to 75 gr and heavier 223 bullets they do about about anything you can do with the larger caliber AR-15 choices. The 6.5 Grendel is the only one that remotely interests me.

To have any real gains in performance you have to move to the AR-10 platform.

What about the following, in an AR15? Still not enough difference over the 5.56?

250gr at 2,200fps

Or

180gr at 2,550fps

I was thinking something similar.

I am trying to envision a world where a 223/5.56 would be a better general purpose hunting rifle than a 450 Bushmaster…..ever.

Most especially, here in the east.

 

[horsey300]

If you had to choose one, what one would it be and why? I’d like to go down the AR rabbit hole a little further with one of these, don’t feel like messing with both. The 300 almost seems more tempting do to the subsonic/supersonic thing. But the other is more economical to shoot. Give me some insight with your knowledge and experience.

Soooo... you CAN load subs for .223, BUT essentially, they're each good in their own roles, an sbr .300 blk with a can is awesome for indoors, and decent with 110s and 125s for deerish sized critters at mediocre ranges, the .223 is decent for deer with same ranges, great for varmints at various ranges and fairly decent for stretching the legs too... if you handload, they're both quite versatile, if I could only do 1 it would be .223 because I spend too much time with coyotes and prairie dogs at ranges I wouldn't attempt with the .300bo. In other parts of the world? .300bo would do everything I'd want.... but rather than trying to crescent wrench things, I believe in tools for purposes.

 

[horsey300]

Yep, you’re right. I do enjoy shooting the 300 but looking for a way to justify it or make better use of it.

Just curious, what kind of terrain do you hunt? Distances?

 

[Space Ghost]

There are a lot of "ifs, and or butts" for each one... however, you asked for "if you had to choose one", so that's the answer I'll give you.


5.56 every day, and twice on Sunday.

It's just vastly more universal, cost effective, and still can do the job required.

In fact, other than being a fun, quiet, expensive toy (with much degraded pistol like energy levels when shooting subs) the 5.56 can do anything the .300 can (and more) with correct ammo selection.

 

[cfullgraf]

I like the 300 BO as a replacement for the 30 Carbine. A bit more powerful but with limited effective range to reduce the chance of collateral damage. I shoot only supersonic 300 BO. But, if you want to go suppressed, the 300 BO does well.

Post war 30 Carbines do not have the best reputation for reliability and I feel a USGI carbine should not but put in a regular shooting role.

Get a 20" or longer barreled 223 Rem AR-15 and go after varmints and other small critters. Get a 1:8 oir 1:7 twist barrels. It works well with 55 grain bullets and will handle the heavier bullets well.

I'm not a fan of the 16" carbine version of the AR-15. For civilian use, the 20" is as easy to handle and you get some velocity boost due to the longer barrel. The military has some specific needs for the shorter barrel. A 20" AR-15 is the rifle of choice for Service Rifle competition these days.

My main prairie dog rifle is a 26" heavy barrel AR-15 chambered in 204 Ruger. I shoot 39-40 grain bullets in it. It shoots a bit flatter out a bit farther than 223 Rem. 223 Rem would be effective as well.

 

[Captains1911]

IMO unless you want to shoot suppressed the 300 BO does nothing for me. In fact, I don't see where any of the other cartridges that you can fit into an AR-15 platform offer enough advantage over 5.56/223 to be worth the trouble.

With an 8 twist barrel you can shoot pretty much any bullet from 50-80 gr. When you get to 75 gr and heavier 223 bullets they do about about anything you can do with the larger caliber AR-15 choices. The 6.5 Grendel is the only one that remotely interests me.

To have any real gains in performance you have to move to the AR-10 platform.

Supersonic 300 BLK is ballistically superior to 5.56/.223 within 150-200 yds, even with a significantly shorter barrel. If all I had was 5.56, I wouldn’t worry too much, but that doesn’t change the fact that 300 BLK does offer advantages at shorter ranges.

OP: if you’re only going to own one, then get 5.56/.223.

 

[FL-NC]

I generally prefer 223/5.56. I bought a discount 300 BLK upper from PSA for $275, but it is only used for hogs and deer, and it does great for those purposes. Good luck finding a decent hunting rifle for $275.

 

[wesmonster]

If cost is your primary factor and you don't reload then 5.56 or 7.62x39.
I'm with mcb, I also shoot multiple calibers out of ARs and each one has their strengths.
300 bo is easy to start with as you're already using same bolt & mags. Specific .300bo mags are really just optimized for short heavy bullets but I've not found an off the shelf commercial load that doesn't work in most 5.56 mags, excluding PMAGs.
.300 bo has less felt concussion/blast in both subs & supers.
S&B and Magtec make good inexpensive range loads in subs and supers. ADI makes a nice load with Sierra matchkings for better accuracy and there's several great hunting loads.
6.5 Grendel is a great caliber, although there's no more steel case being imported I read that S& B is making brass case ammo for cheap range use.
9mm is certainly a cheap option but blowback isn't the same as a DI setup, and at 100 yards you'll see the difference in the 300 bo's better bullet coefficient at 100 yards.

 

[BreechFace]

If you had to choose one, what one would it be and why? I’d like to go down the AR rabbit hole a little further with one of these, don’t feel like messing with both. The 300 almost seems more tempting do to the subsonic/supersonic thing. But the other is more economical to shoot. Give me some insight with your knowledge and experience.

All depends on use (varmints, SHTF, training, etc.), abilities (reloading, tuning, smithing, etc), and desires. Sounds to me like you are dipping your toe in the water on the AR platform, if that is the case I think the first option below is your best introduction.

For one's first AR, I would go with, minus some caveats below:
5.56, 16" 1:8 twist, mid-length gas, "hanson" profile, 15" lightweight MLOK handguard
Dial it in with 77gr OTM, shoot 55gr for affordability.

If you have a suppressor and reload, a pistol or SBR AR in 300 BLK is pretty hard to beat for versatility (supers and subs), stingyness (very cheap to reload for, and can take use of powder coated lead cast subs), quiet and fun.
300 AAC, 8-9" barrel, 1:7 twist, pistol-length gas, SLR adjustable gas block, medium profile, Midwest Industries 12" Suppressor diameter MLOK Rail

 

[Barnfixer]

Just curious, what kind of terrain do you hunt? Distances?

Rolling to flat farmland, some wooded area. Shots to 250 yards or less.

 

[Lo-Profile]

I have too many AR's in 6-7 calibers
2 are 300 blackout. My Get Home/EDC bag has a Aero build 8" with a law folding adapter. Fits in a 20" sling pack, with 3 extra mags and a med kit, light, lifestraw bottle and some grub

 

[horsey300]

I do have both, it is addictive! I keep bouncing around on what one I should setup for more serious purposes (possibly coyote & varmint hunting) and the other for plinking.

With THIS in mind and your stated terrain, run the .223 for varmints and the .300bo as a plinker.

 

[Chuck R.]

I like supersonic 300 blackout a lot because it produces a recoil impulse very similar to 223, but with a lot softer muzzle blast, and is a better performer in a short barrel. My home defense/3 gun rifle is a 13.75" 8 twist 300 blackout with carbine gas and a krinkov brake pinned and welded to 16". Very handy rifle and still produces 2400 fps with a 110 vmax out of a very compact package. I have shot it indoors and it doesn't pound on your ears like a 16" 223 does, and a 110gr v max at 2400 is very terminally effective.

I like 7.62x39 in an AR a lot too but I can shoot the 300 blackout a lot faster than a 7.62x39 because the 300 blk has quite a bit softer of a recoil impulse to me. The 7.62x39 wins out in power for hunting, but I think 300 blackout is a better defensive cartridge because it has such a soft recoil impulse and is probably more reliable feeding in 30 round mags.

I have played a little bit with subsonic 300 blackout but it really doesn't do much for me. Considering the cost of good subsonic expanding .308 bullets I prefer to just shoot 147 gr 9mm suppressed.

Agree 100%.

In a short barrel, the 300 Blackout is the way to go IMHO. I get 2170 out of a 9" barrel with 110s. Can't touch that with a 9" barreled 5.56. The compact carbine/pistol makes a great HD gun and with a linear comp isn't as bad on the ears as a short barreled 5.56.

For a general all-around gun, I prefer a .223 with the Wylde chamber, but like everything else, it comes down to task/purpose.

 

[mavracer]

Having both is the correct answer. But I'm with you @Barnfixer just one or the other I might go for the Blackout for the versatility.

 

[Mercy Me]

If you're suppressing it, 300 subs are close to Hollywood quiet. It suppresses very well, certainly better than 5.56. And you can get some good terminal effect from a very short barrel, the same of which could be said for 7.62x39 but not 5.56.

That said as a general purpose round I think 5.56 is superior. Better ballistics, better performance at range, cheaper/more readily available, shoots flatter, etc.

 

[JShirley]

As a couple of people have said, if you want a pistol, .300 is a better choice, as well as if you want to shoot subsonics. if you just want something to pop deer out to 150 m, 300 is fine. if you want a more versatile round, 5.56 is the way to go.

I've had two 7.62x39mms that were not in communist block- style rifles. Neither of them worked.

John

 

[Ignition Override]

Ammo prices have determined vast numbers of guns- as with most of mine.

If .223 vs 300 BO…..bulk ammo prices.. More ammo for me always equals more fun, and we have absolutely No Actual Idea when—or which type—of the next single event will send people stampeding to search engines like Ammoseek, or to Academy.