Any thoughts on a 300 Blackout?

[funnsun34]

So I plan to start work on my first 80% lower this weekend. I have everything for a 5.56/223, however I bought 2 lowers so I was wondering what the consensus is
on building a 300 Blackout. Would it be work it since I already have a AR-10 .308.

thx

I'll post pics once I have the lower milled out.

 

[Biggfoot44]

You can use the same lower for 5.56 and .300 Whisper/ Blckout , provided both are same configuration , ie pistol and pistol or HBAR and HBAR .

I am almost never *that guy* who harps about the search feature , but the .300 has been a VERY popular topic. The very brief summary is lots of people have them , and generally like them a lot.

 

[Klunatic]

Would it work for what? Not sure what you are asking. 300Blk is a great round to shoot suppressed subsonic. If your looking for a hunting rifle that kicks less than a .308 then yes it will work. I found its a great first hunting round for kids, especially if you shoot suppressed.

 

[funnsun34]

I'm just wondering if it's worth building. Like I said I have 2x 80% lowers that I plan to start working on this weekend. I bought 1x 556 upper. I thought about buying a 300 blk upper but I have never shot one before. No hunting for now, just target.

 

[DaemonAssassin]

I'm just wondering if it's worth building. Like I said I have 2x 80% lowers that I plan to start working on this weekend. I bought 1x 556 upper. I thought about buying a 300 blk upper but I have never shot one before. No hunting for now, just target.

If you get a good barrel, it can make a decent target rifle. If you reload you can tune the loads to your barrel. Also an added advantage to reloading for .300BLK and .308 is that they use the same bullets.

I have a 300BLK upper and I love how I can do a caliber change, by swapping uppers and mags. I built my 300 for hunting only but it get some incredible accuracy, with the right ammo.

If you do decide to get into the 300BLK game, be sure to get a barrel with a pistol length gas system, so you can use supers or subs, without any serious issues.

 

[fidelity]

Here's a 300 BLK barrel (with gas system and flash hider) for $220 (that DA and I were recently discussing) ...

http://www.recoilgunworks.com/barrel-assembly-blackout-p-29643.html

 

[swinokur]

I have a DD 300 BLK carbine. I shoot subs out of it with a can. Nice rifle

I had an Engage lower I bought a DD MK 18 in 5.56 for. Engage built a 300 BLK 10.5 upper for it. Shoot subs and regular ammo w/o issue. You'll enjoy it. As noted, a pistol length gas system works with both subs and supers.

 

[Pinecone]

My stamp just came back for my ThunderBeast CB5.

So now have to change to the short barrel on my .300 BO rifle. I am looking forward to playing with it.

I do have to work down some sub sonic loads.

 

[Bootknife]

The good thing is a 300 BO upper Mil Spec will Snap right on Your MS lower and use the same Magazines . I bought a DD upper in 300BO and Put it on My Best Triggered Lower for a Supper Fun Gun that includes an AAC Can. Very versatile Rig . Back on My 25-45 Sharps Upper for a 300Yd. A$$ kicker. Take the Can off and put it On My Rem R5 Bolt Gun to Reach Out Quietly. The 25-45 Sharps is a necked up 5.56mm. to .257 Caliber, so it takes the Same Mags as well.

 

[Klunatic]

I'm just wondering if it's worth building. Like I said I have 2x 80% lowers that I plan to start working on this weekend. I bought 1x 556 upper. I thought about buying a 300 blk upper but I have never shot one before. No hunting for now, just target.

Definitely worth doing, you can buy ammo off the shelf or roll your own as suggested above. I recommend rolling your own if you can to get the most out of the rifle. It is the cheapest other caliber you can build for your lower. Same mags, bolt just a different barrel. I love my 300blk for hunting. Its a tack driver for target shooting as well.

 

[Bootknife]

They are selling the 25-45 Sharps barrels @ Sharps Rifle Co, as well and it uses the same Action , Bolt, Magazines ETC. You Only Have to Change the Barrel! Check out their page...www.srcarms.com

 

[jimbobborg]

Make sure you mark the mags you put the 300 in so you don't accidentally load it in a 5.56 upper. Some Blackout ammo will chamber in a 5.56 barrel with bad results.

And before someone jumps all over my statement, the second to last 300 BLK discussion I mentioned it and several other members confirmed it.

 

[swinokur]

good point. I have little "3" labels on the bottom of mine.

 

[Slowhand]

Make sure you mark the mags you put the 300 in so you don't accidentally load it in a 5.56 upper. Some Blackout ammo will chamber in a 5.56 barrel with bad results.

And before someone jumps all over my statement, the second to last 300 BLK discussion I mentioned it and several other members confirmed it.

2nd this! Use different COLOR mags AND Labels.

 

[funnsun34]

Thanks all for the input! From some of the post that I read, I really need to find more info on the MD laws regarding what I can BUILD so that I stay legal.

 

[babalou]

I believe the 300 is not under the same rules as a .223/5.56 upper with respect to HBAR or not. Also, I had a long conversation with Clandestine about it. It was his recommendation for me to do a .300. I was seriously looking at building out a 6.8 or 6.5. He said that those are great rounds but for ease of use and cost, a .300 would be awesome. It hits well and he debunked some of the things said about it. Has the same Bolt, mags, etc. So, my next upper is going to be a CMMG upper .300. Has anyone had issues with the CMMG complete uppers?

Oh, and as the other folks on have said, one you start, it is like crack- you need to have more. It never ends. LOL.

 

[Klunatic]

I use these bands for my 300 BLK mags. http://www.ebay.com/itm/141257267785?ssPageName=STRK:MESELX:IT&_trksid=p3984.m1555.l2649

 

[funnsun34]

That's what is driving me nuts, what are the MD Laws on building your own AR's. I've been searching for hours on end. I keep coming up with out of take info or completely irrelevant.
All I know is 16in HBAR, and 10rds mags. Surely there has to be a website that has a list. I'm only talking about rifles not pistols. I've seen parts of the law on this site but nothing that pertains to building your own.

The state of MD kills me.

 

[DaemonAssassin]

That's what is driving me nuts, what are the MD Laws on building your own AR's. I've been searching for hours on end. I keep coming up with out of take info or completely irrelevant.
All I know is 16in HBAR, and 10rds mags. Surely there has to be a website that has a list. I'm only talking about rifles not pistols. I've seen parts of the law on this site but nothing that pertains to building your own.

The state of MD kills me.

Because it is not a 223/556, you can use whatever barrel profile you want for the 300 BLK. You don't have to worry about barrel profile for anything except a 223/556.

If you are anywhere near by, I'd be willing to help you through it all.

 

[Merlin593]

I've got a 16" .300 blackout for deer hunting. Bought the complete upper and pinned it onto an Adcor lower. Packs a good punch on the deer. I want to try hog hunting with it one day too.
Lots of options out there for complete uppers...
Not sure what barrel length you're thinking (need to decide on a pistol or rifle) of but 7.5" pistol would pretty much be a range toy/flame thrower. I'd recommend 10.5" for a pistol or longer for rifle depending on the purpose - HD/hunting/suppressing
Great round and a lot fun to shoot!
The ammo is just a bit more expensive than 5.56/.223.