300 Blackout Upper vs. Barrel

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frudoc

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I have an M&P 15 Sport and I would like to get either a 300 Blackout upper or barrel for it so that I can use a suppressor (one that already works with a 9mm). That said, I am new to all of this and have a question:

I believe all I need is a 300 Blackout barrel, which I believe I can afford. But what would be the advantage to getting an entire 300 Blackout upper (which I probably cannot afford *S*)?

Also, if you are up for it, do you have any recommendations for specific barrels and uppers I should be looking at? I am googling like mad, but always appreciate your experience and expertise to help me save time and have more piece of mind.

Thanks!
 
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Well, the biggest benefit to a complete upper would be the ability to change out calibers quickly.
Also, wouldn't have to re sight in after caliber change.
As to barrels and uppers, I'd be good with CMMG, either for complete upper or just the barrel.
 
There is a big difference between changing barrels and changing uppers.... You have to have the tools and knowledge to change out an AR barrel but only push out a few pins to change an upper. Also, you mentioned using a 9mm suppressor on a 300 blackout. First, the 9mm will be treaded 1/2x28 and the Blackout will be threaded 5/8x24. Then you need to consider the pressure from a rifle load going through a pistol suppressor... call the suppressor manufacturer but Im betting they say dont do it.
 
frudoc said:
I have an M&P 15 Sport and I would like to get either a 300 Blackout upper or barrel for it so that I can use a suppressor (one that already works with a 9mm). That said, I am new to all of this and have a question:

I believe all I need is a 300 Blackout barrel, which I believe I can afford. But what would be the advantage to getting an entire 300 Blackout upper (which I probably cannot afford *S*)?

Also, if you are up for it, do you have any recommendations for specific barrels and uppers I should be looking at? I am googling like mad, but always appreciate your experience and expertise to help me save time and have more piece of mind.

Thanks!
Click to expand...


Just saying...

DSA ZM4 Forged 7075T6 A3 AR15 Upper Receiver; 300BLK - ZM4CBU300-D S Arms
 
Stebo said:
Wow, that's another definition of "inexpensive". How do they make any money off of that? Just randomly looking around the internet I figured between $400 - $450 for parts, but that was with a $200 barrel.
Click to expand...

Take note that it doesn't include a bcg or charging handle. That's why it's so cheap.
 
Thanks everyone for the replies. It will give me some reading to do tonight. As far as the suppressor compatibility is concerned, the dealer I have been working with has experience with the set up I am talking about, so I am not worrying too much about that yet (but I will verify everything later!). Mostly here I am just trying to learn more about barrels vs. uppers, before I start working more with him. I'm hoping to learn a little something, which all of you are helping me with!

Thanks!
 
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Since your M&P Sport is 5.56, you can use your existing BCG and charging handle in the upper that doesn't have it. So you could just purchase the DSA semi-complete upper. 300 Blackout uses the firing control parts as 5.56/223. Only need a barrel change.

This is the route I'm going, but opposite. I have a 300 Blackout (for hunting) and will be picking up a 5.56 upper for it so I can go plinking at the range.
 
frdfandc said:
Since your M&P Sport is 5.56, you can use your existing BCG and charging handle in the upper that doesn't have it. So you could just purchase the DSA semi-complete upper. 300 Blackout uses the firing control parts as 5.56/223. Only need a barrel change.

This is the route I'm going, but opposite. I have a 300 Blackout (for hunting) and will be picking up a 5.56 upper for it so I can go plinking at the range.
Click to expand...

Oh really? So, to be redundant, er, clear (LOL!) I can get an upper without the BCG and charging handle and just use my existing one?

Does that require a significantly increased level of expertise to install? I think I could afford that, and I really like the idea of a (for the most part) more simple installation compared to installing a barrel.

I know even less about good retailers than I do about barrels and uppers right now, but I am finding places like Model 1 Sales and others that seem to offer the upper without all the parts. Are there retailers I should stick with and ones I should avoid with this stuff generally speaking?
 
Also, FWIW, I would really like to have a longer handguard on whatever I get so that I have the option of placing a light further down the barrel. Something more like this style. I am assuming that is fine and I can get whatever I want when it comes to this?
 
Removal and installation of a BCG and charging handle should be commonplace when dealing with an AR. After all, you should know how to disassemble your upper when cleaning.

With the .300 Blackout, you can even use your existing magazines. The cartridge is just a resized 5.56 casing to hold a 30 cal bullet.

I would go complete upper minus the BCG at minimal over just a barrel swap. With a barrel swap, you will need to make sure that the gas system is the correct length to fire the 300 Blackout cartridge. With a complete upper, it's already done for you (counting out any type of manufacturing flaws).
 
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frdfandc said:
Removal and installation of a BCG and charging handle should be commonplace when dealing with an AR. After all, you should know how to disassemble your upper when cleaning.

With the .300 Blackout, you can even use your existing magazines. The cartridge is just a resized 5.56 casing to hold a 30 cal bullet.

I would go complete upper minus the BCG at minimal over just a barrel swap. With a barrel swap, you will need to make sure that the gas system is the correct length to fire the 300 Blackout cartridge. With a complete upper, it's already done for you (counting out any type of manufacturing flaws).
Click to expand...

Sounds like that's the way to go. Thanks so much. Now I have the direction I was hoping for.


For anyone, any specific recommendations, experiences with retailers or brands, etc. would be appreciated!
 
CMMG is a great company that does 300 Blackout. And they are more budget than others and make a great product for the dollar. Their complete uppers start around $570.

There are other companies as well.

Noveske, Daniel Defense, Advanced Armament and a few others. But they are going to be over 1K.

Not sure what your budget is, but I follow the rule "Buy once, cry once". You get what you pay for.
 
frdfandc said:
CMMG is a great company that does 300 Blackout. And they are more budget than others and make a great product for the dollar. Their complete uppers start around $570.
Click to expand...

$600 is about tops. Less would be great; but I too like to buy the best quality I can afford -- "afford" being the operative word right now.

That said, when you say "complete" uppers, you mean that they include the BCG and charger too, correct? If this is the case, and I can just use my existing BCG and charger, I am guessing that something int he $400 range should be possible.

I will start looking for CMMG now. Thanks!
 
IF you want to use the same carrier fine, but do not use the same bolt with both barrels.
Bolts wear in with one barrel over time, if you use the same bolt with both the 300 and 5.56 you may have headspacing issues.
 
Gunslinger808 said:
IF you want to use the same carrier fine, but do not use the same bolt with both barrels.
Bolts wear in with one barrel over time, if you use the same bolt with both the 300 and 5.56 you may have headspacing issues.
Click to expand...

Interesting. Good to know. As it is, I have not even shot this Sport yet. I may not use it until I get the upper. I assume that if I hold off I won't have to be concerned about the bolt.

Thanks.
 
I myself would get a BCG and Charging handle for the new upper, That way everything wears in as a complete unit. Using the same BCG with both uppers is going to cause accelerated wear on the new upper and could conceivably cause bolt lock an unlock problems in the future. Where with separate "complete" uppers that problem wouldnt exist.
 
frdfandc said:
Since your M&P Sport is 5.56, you can use your existing BCG and charging handle in the upper that doesn't have it. So you could just purchase the DSA semi-complete upper. 300 Blackout uses the firing control parts as 5.56/223. Only need a barrel change.

This is the route I'm going, but opposite. I have a 300 Blackout (for hunting) and will be picking up a 5.56 upper for it so I can go plinking at the range.
Click to expand...

I would be very hesitant to switch a BCG back and forth between two different uppers. There are some guidelines out there as for when you can use barrels and BCGs in different stages of their life (new vs. used) and I don't recall the scenario where rotating a BCG back and forth between two uppers is a recommended practice. Actually, I wouldn't do it myself.
 
It could develop headspacing issues. But that would depend on the number of rounds through the 5.56 before being used. If it's a new BCG in the Sport, then your GTG. If it has a lot of rounds, go with a new bolt, but you can use the carrier without issue.
 
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