Talk me into or out of 300blk...

[DaveTheMinion]

So, from research, 300blk has nearly identical ballistics as 7.62x39, but slightly better efficiency at long ranges (although I'm not sure if they're comparing match grade 300blk to surplus, target, or match grade)
I'm already waiting on my upper from ccf chambered in 7.62x39, as a plinker/possible deer/hog maybe even yote slayer. Steel case ammo for 7.62 is dirt cheap for target/plinking, and I won't be burning through much high end hunting ammo.

That being said, 300blk seems to really only have the advantage of being suppressed easily with subsonic rounds. Are there sources that will make the 300blk a more popular caliber that will drive cost down?Basically, I plan on building another ar in a different caliber, might just go the 556 route so ill have one in 7.62, one in 22, and one in 556, any thoughts? How bout 5.45?? What are 5.45 uppers going for?

 

[Jbum]

300 blk you can slap on a 223/556 lower and use the same mags.

 

[sovietak474u]

Cost will never go down on any caliber ammo. Much less an oddball like 300blk.

 

[dial1911]

The 300 blackout case is based on a .221 Fireball- which is based on a .223... I would assume this means the same bolt face size (hence same bolt) and same magazines as are used for standard .223... probably easier to find than 7.62x39 AR parts.

Other than that, cheap ammo is a huge reason for me to go with one caliber over the other. I've gotten rid of almost everything that I am not set up to reload for. I found that the Mini-30 I had ate it's own value in ammo too quickly. Thank goodness I only had a five round magazine for it.

 

[Laxguy59]

If...
-the ability to shoot 125gr to subsonic 240gr gives you no benefit

-the reloading capabilities like the ability to convert 5.56 to 300blk or wide array of projectiles since it used 308 pills, is of no importance to you

-the ability to use 556 mags and bcgs doesn't concern you.

Then go with the Russian.

 

[Chuckdog]

Unless you intend to add a can and run subsonics, I see no benefit to the 300? It's an ok caliber, but performance wise you can do a lot better with other choices. Yes, I own one. Yes it shoots very good. The accuracy is surprisingly good, but velocity wise, it ain't never gonna be a barn burner.

The 6.8 spc is by far my favorite choice in the AR15 size platform.

 

[user 71]

I was in the same boat as you but decided to go through with it.

Biggest benefits:
-Works very well with the AR platform (7.62x39 is hit-or-miss, I've heard both good and bad stories).
-I can use the numerous 5.56 mags that I already have.
-Doesn't use an oddball BCG.

Biggest drawbacks:
-Cost. It's still ~$.50 / round with the cheapest stuff I can find.
-Confusion on which rounds/weights will or will not cycle a carbine, un-surpressed gas system. I would prefer not to pay $10-30 to find out. 115 grain supers work well, I may try 125's.

 

[Tech Jacket]

300 blk you can slap on a 223/556 lower and use the same mags.

there are several good points on the thread and this is one. Tac TV did a really good episode on the 300 blackout you might could find on line. hardly definative but very informative.

 

[Laxguy59]

I was in the same boat as you but decided to go through with it.

Biggest benefits:
-Works very well with the AR platform (7.62x39 is hit-or-miss, I've heard both good and bad stories).
-I can use the numerous 5.56 mags that I already have.
-Doesn't use an oddball BCG.

Biggest drawbacks:
-Cost. It's still ~$.50 / round with the cheapest stuff I can find.
-Confusion on which rounds/weights will or will not cycle a carbine, un-surpressed gas system. I would prefer not to pay $10-30 to find out. 115 grain supers work well, I may try 125's.

A correctly built upper will cycle all weights.

 

[maxpaynya]

My sofa stainless upper with Remington plinking will hold a nine inch group at 300 yards on iron sights.