Convert AR15 223 to 6 ARC?

Arken7mm

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I'm not familiar with 6mm ARC. Is it possible to shoot the 6mm ARC out of a AR15 chambered in 223/556 stock or with a few modifications or do I need to buy a completely new AR15 specifically chambered and designed for 6mm ARC?

I know with the 7mm PRC and 300 PRC you can swap out the bolt and fire it in the same rifle, can you do something similar with that with 223/556 and 6mm ARC?
 
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You would need a new bolt (minimum) but I would replace the whole bolt carrier group and obviously a barrel. You can squeak by with pmags for a few rounds but would be better off with arc specific mags for better reliability.
 
OP
Arken7mm

Arken7mm

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Well, it's probably best to just buy a different AR then. Less hassle and less chances of malfunctions.
 

Tobe_B

Lil-Rokslider
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BCG, Barrel, And mags. If you didn’t want to build an all new rifle, just build a new upper. My ARC shoots on my 5.56 lower just fine, and my 5.56 shoots on my ARC lower just fine. Only difference between my lowers is the buffer.

I’ve got a lighter buffer in the ARC since I went with a rifle length gas system. But it still cycles fine with the H3 in my 5.56.


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ChrisAU

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I'm not familiar with 6mm ARC. Is it possible to shoot the 6mm ARC out of a AR15 chambered in 223/556 stock or with a few modifications or do I need to buy a completely new AR15 specifically chambered and designed for 6mm ARC?

I know with the 7mm PRC and 300 PRC you can swap out the bolt and fire it in the same rifle, can you do something similar with that with 223/556 and 6mm ARC?

I wanted to make sure this was addressed - that is not true at all. You will 1000% also require a barrel change in any weapon to change from 7PRC to 300PRC.
 

MThuntr

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I'm not familiar with 6mm ARC. Is it possible to shoot the 6mm ARC out of a AR15 chambered in 223/556 stock or with a few modifications or do I need to buy a completely new AR15 specifically chambered and designed for 6mm ARC?

I know with the 7mm PRC and 300 PRC you can swap out the bolt and fire it in the same rifle, can you do something similar with that with 223/556 and 6mm ARC?
Just buy a complete 6mmARC upper or a complete rifle. It seems you don't have a solid grasp on much of the basics of firearms so it's safest that you don't tinker.
 

WKR

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BCG, Barrel, And mags. If you didn’t want to build an all new rifle, just build a new upper. My ARC shoots on my 5.56 lower just fine, and my 5.56 shoots on my ARC lower just fine. Only difference between my lowers is the buffer.

I’ve got a lighter buffer in the ARC since I went with a rifle length gas system. But it still cycles fine with the H3 in my 5.56.


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You don't need to swap the entire BCG, only the bolt. The carrier is the same.
 

WCB

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Just buy a whole new AR...unless money is an issue I don't get the upper swap thing.
 
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I bought a 6mm ARC upper minus the bolt carrier and just ordered a bolt. I kept the charging handle and bolt carrier from the 5.56 upper. Going this route was less than buying an entire rifle. I also got a 3lb Velocity drop-in trigger.
 

WKR

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I'm not familiar with 6mm ARC. Is it possible to shoot the 6mm ARC out of a AR15 chambered in 223/556 stock or with a few modifications or do I need to buy a completely new AR15 specifically chambered and designed for 6mm ARC?

I know with the 7mm PRC and 300 PRC you can swap out the bolt and fire it in the same rifle, can you do something similar with that with 223/556 and 6mm ARC?
First off,, 7mm prc and 300 prc use the same bolt face. But please don't listen to whoever told you that. That would be a mistake you only made once because you might not ever have a chance to make it again.

Don't swap bolts and think you can shoot a 7 through a 300 or vice versa. You would need to swap chambered barrels.

Edit: I dont think a 300 would even chamber in a 7 but either way, don't try it.
 
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First warning sign is when OP asked if he can shoot a 6mm projectile down a 5.56mm bore. Not trying to be mean but you might need to go back to basics.
 
OP
Arken7mm

Arken7mm

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Have any of you done any suppressed shooting with 6mm arc and compared it to 223/556 with regards to db ? I'm trying to figure out which would be a better all around multipurpose rifle for home defense and hunting.
 

zdc1775

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Have any of you done any suppressed shooting with 6mm arc and compared it to 223/556 with regards to db ? I'm trying to figure out which would be a better all around multipurpose rifle for home defense and hunting.

I have both, but haven't shot the 6ARC suppressed yet. Even if it were quieter I would still choose 223 for multipurpose use.
 

Unckebob

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Have any of you done any suppressed shooting with 6mm arc and compared it to 223/556 with regards to db ? I'm trying to figure out which would be a better all around multipurpose rifle for home defense and hunting.

I use mine for target practice, but would definitely use it for up to deer sized game if my rifle wasn't so heavy.

For home defense, I would pick a 223 because of the proven, reliable operation they have.
 
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