2 piece 9mm AR Bolt?

Howard Law

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I dig it, especially the increased mass. How many pieces is a 5.56 bcg?
 

Cudruln

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I would be willing to give it a shot. Especially if you have the nfa ar9 lower. Seems to me they would make something that would work with their own products.
 

DarthVader

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Thoughts?

9mm New Frontier Armory Modular AR BCG

http://www.joeboboutfitters.com/New...ar_9mm_Bolt_Carrier_p/nfa-ar9-modular-bcg.htm

I immediately hesitated at the thought of a two piece bcg.

@DarthVader?
Not sure why I didn't get a notification on this sooner. I'd like to see one of these on high speed film. It doesn't look like the halves mate together as a single unit. The idea of being able to switch the bolt face out to shoot 40 S&W or 45 ACP is pretty interesting. To me, a caliber change is going to be an upper swap anyway, so why not just run separate, complete upper groups. And you'd have to buy separate bolt heads, so that eats into any cost savings.

But I think the bigger question is one of possible bolt bounce and reliability. The unit would likely travel backwards as a single unit. But I wonder if the the impacts as the carrier hits it's max rear travel would jolt them apart slightly? Or if they would separate as the carrier travels forward and impacts the barrel extension? Often, the forward impact causes a regular AR BCG to bounce backwards slightly before coming to its final position, locked into the extension. This is usually exacerbated with over gassing and high carrier speeds. A heavy buffer or increased power buffer spring can usually tame it. And it is usually only an issue with full auto fire.

Honestly though, is this a solution looking for a problem? It's not often that we see an AR pattern subgun in anything other than 9mm. Or maybe NFA just tipped their hand and intend to expand their offerings to other calibers and complete uppers.
I dig it, especially the increased mass. How many pieces is a 5.56 bcg?
Sort of the same thing, but not really. The bolt is designed for linear movement within an AR carrier, but the 9mm carrier isn't. I guess I'd like to see one run on FA just to see what happens.
 

DarthVader

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A couple of good videos demonstrating bolt bounce

I suppose the question is, what would this look like if the carrier were two separate reciprocating parts?


 

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Not sure why I didn't get a notification on this sooner. I'd like to see one of these on high speed film. It doesn't look like the halves mate together as a single unit. The idea of being able to switch the bolt face out to shoot 40 S&W or 45 ACP is pretty interesting. To me, a caliber change is going to be an upper swap anyway, so why not just run separate, complete upper groups. And you'd have to buy separate bolt heads, so that eats into any cost savings.

But I think the bigger question is one of possible bolt bounce and reliability. The unit would likely travel backwards as a single unit. But I wonder if the the impacts as the carrier hits it's max rear travel would jolt them apart slightly? Or if they would separate as the carrier travels forward and impacts the barrel extension? Often, the forward impact causes a regular AR BCG to bounce backwards slightly before coming to its final position, locked into the extension. This is usually exacerbated with over gassing and high carrier speeds. A heavy buffer or increased power buffer spring can usually tame it. And it is usually only an issue with full auto fire.

Honestly though, is this a solution looking for a problem? It's not often that we see an AR pattern subgun in anything other than 9mm. Or maybe NFA just tipped their hand and intend to expand their offerings to other calibers and complete uppers.

Sort of the same thing, but not really. The bolt is designed for linear movement within an AR carrier, but the 9mm carrier isn't. I guess I'd like to see one run on FA just to see what happens.



Oh I don't really care one way or the other, I was just being disagreeable with @rOmiLaYu for the sake of being disagreeable.
 
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DarthVader

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LOL!

PS: I know you know the difference. Didn't mean for that to sound like I was pontificating in response to you. But I am curious what you think about it.
 
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rOmiLaYu

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It doesn't look like the halves mate together as a single unit.
It doesn't look that way to me either...which makes me wonder about...

bolt bounce and reliability.
and....

Honestly though, is this a solution looking for a problem? It's not often that we see an AR pattern subgun in anything other than 9mm. Or maybe NFA just tipped their hand and intend to expand their offerings to other calibers and complete uppers
Yup, had that thought, too. Actually, I had exactly the same thoughts you did.

I think I'll pass.
 
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Willy Leadwell

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I haven't seen one thing that would indicate to me that I should own one of these. I don't even get what purpose it's supposed to serve.
 

PewPewPewCo

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I haven't seen one thing that would indicate to me that I should own one of these. I don't even get what purpose it's supposed to serve.
9mm AR's are stupid fun to suppress. and with NFA arms new glock lower and glock cut bolt its a great time to jump in at a low price.
 

DarthVader

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I haven't seen one thing that would indicate to me that I should own one of these. I don't even get what purpose it's supposed to serve.
The only advantage I see, assuming that it doesn't create any reliability issues, is that you can easily swap the bolt face for other calibers. And if they were so inclined, they could offer different weight carrier tails. But someone would need to offer uppers in other calibers for any of that to matter.
 

NWS

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9mm AR's are stupid fun to suppress. and with NFA arms new glock lower and glock cut bolt its a great time to jump in at a low price.


Yeah, kinda pissed all this came out right after I dumped all the money on a Hahn block and 9mm upper.
 

NWS

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I have a suppressed 9mm SBR. I still don't understand how this bolt helps me.


If you didn't have one, it is a cheaper alternative than what was already on the market plus apparently it has increased mass and the ability to change calibers down the road.
 

Willy Leadwell

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The only advantage I see, assuming that it doesn't create any reliability issues, is that you can easily swap the bolt face for other calibers. And if they were so inclined, they could offer different weight carrier tails. But someone would need to offer uppers in other calibers for any of that to matter.
so what you're saying is that they've found a complicated way to simplify things a bit?
 

PewPewPewCo

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The only advantage I see, assuming that it doesn't create any reliability issues, is that you can easily swap the bolt face for other calibers. And if they were so inclined, they could offer different weight carrier tails. But someone would need to offer uppers in other calibers for any of that to matter.
Qcircle10 sells 40, 10mm, and 357 sig uppers

I believe their 45 upper is on its way out soon as well if not already out
 

Willy Leadwell

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If you didn't have one, it is a cheaper alternative than what was already on the market plus apparently it has increased mass and the ability to change calibers down the road.
So it's super easy to change the bolt, but I still have to change the barrel, or have multiple uppers that share a bolt?