6mm ARC - AR Build?

Starline just released their 6 ARC brass… mine should be here Wednesday. I'll post up a photo of my 6 ARC build soon. I threw it together a couple of months ago, but never had a chance to shoot it before moving from Cleveland. We just rolled into Billings, MT last night and look forward to having more opportunities to shoot. From all I've heard, the 6 ARC is a great little round!
The website shows sold out already. Thankfully I found some loaded ammo so I will get brass from that.
 
Just another point of view. I'm an AR guy and my most accurate ones tend to be be my match grade with 11 degree target crowns vs my threaded brake ones. If you really think about it my .224, 6mm, and 308 don't kick enough to need a brake and they are much more friendly to both me and other people when shooting. muzzle brakes are abusive :)

Like I said I made my ARC for PD hunting hence the up to 87 gr varmint pills. The ARC is really slow with heavy pills compared to my 26 inch 243 which is my long range antelope choice
 
Just another point of view. I'm an AR guy and my most accurate ones tend to be be my match grade with 11 degree target crowns vs my threaded brake ones. If you really think about it my .224, 6mm, and 308 don't kick enough to need a brake and they are much more friendly to both me and other people when shooting. muzzle brakes are abusive :)

Like I said I made my ARC for PD hunting hence the up to 87 gr varmint pills. The ARC is really slow with heavy pills compared to my 26 inch 243 which is my long range antelope choice
My son's ARC will have a brake because it will be the quick change adapter for a suppressor.
 
Just another point of view. I'm an AR guy and my most accurate ones tend to be be my match grade with 11 degree target crowns vs my threaded brake ones. If you really think about it my .224, 6mm, and 308 don't kick enough to need a brake and they are much more friendly to both me and other people when shooting. muzzle brakes are abusive :)

Even on my KAC SR-15 LPR, the Silencerco ASR brake cuts my split times between shots when shooting cow-chasing/calf-killing dogs. Being able to hit one at the top of its bound and watch the flight path as the bullet 'dumps' the dog dead in its tracks is nice. 👍

Required, no. Ideal on a square range with other shooters, no. Out "in the field" doing real work with your rifle, super nice! Plus, it is nice for tossing a can on to cut the blast when you don't want to disturb neighbors with too many tours of duty in the sand piles of the Mid-East.

In terms of accuracy, if your threaded barrel is not as accurate as your target crowns, you need a different person doing the threading or need to buy your barrels somewhere else. My friend who shot competition in the military complained he could not really zero my scope. He had a perfect square of 3-shots at each corner of the "box" with the bullseye in the center. Yep, each click on my ACOG walked the group to the four corners. That KAC/Krieger barrel will "shoot the lights out" and suffers no accuracy loss due to being threaded.

And no, this is not a 1" bull barrel. Closest profile is generally a Ranger profile with it being a true mid-weight that swings exceptionally well and is super stable in my hands without being too heavy.
 
Finally unpacking from the move. Here's my recent 6 ARC build:

- Wilde Arms builders set (upper, lower, and 15" handguard in tungsten)
- Proof 18" carbon, rifle + 1 gas
- Aero Ambi charging handle
- Aero complete BCG
- Riflespeed adjustable gas block
- Triggertech Diamond single stage
- Magpul PRS Gen 3 stock and K2+ grip
- Leupold Mark 5 HD 3.8-16x


Probably won't have the chance to try it out until the weekend, but definitely looking forward to it. I have plenty of factory rounds to test out before moving to handloads. Once I see how it shoots, I'll toss my thermal on for some night time fun!


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Finally unpacking from the move. Here's my recent 6 ARC build:

- Wilde Arms builders set (upper, lower, and 15" handguard in tungsten)
- Proof 18" carbon, rifle + 1 gas
- Aero Ambi charging handle
- Aero complete BCG
- Riflespeed adjustable gas block
- Triggertech Diamond single stage
- Magpul PRS Gen 3 stock and K2+ grip
- Leupold Mark 5 HD 3.8-16x


Probably won't have the chance to try it out until the weekend, but definitely looking forward to it. I have plenty of factory rounds to test out before moving to handloads. Once I see how it shoots, I'll toss my thermal on for some night time fun!


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Very nice.

I wonder how big the gas port being it is just around 4 inches to muzzle. My guess it is around 0.10x

Did you happen to check out the gas port size? At Proof they know what they are doing
 
Very nice.

I wonder how big the gas port being it is just around 4 inches to muzzle. My guess it is around 0.10x

Did you happen to check out the gas port size? At Proof they know what they are doing

Looks like port size is .096 per Proofs online specs. Should be nice to fine tune with the AGB and my suppressor.
 
@Hoss50 the kid's 18 inch custom barrel will ship on Monday.

Just some updates for the rest. I sent these pictures to Harley.

Yesterday I function tested it, a club member provided some factory ammo and handloads. I used the ammo to get it close to the middle. After boresighting, first round out of the barrel is in between the two targets. After I got it close enough, I used the handloads and aimed at the top right diamond. First shot is at 7 o'clock of the group. Then the last 4. The last 3 shots clustered nicely, two went in the same hole.

Called it good for the day in the 3 digit temp. Close enough that I can ship the barrel out. Kid should be happy.

Target picture is just through the spotter.

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The 6mm ARC for my son is now finished for phase 1. Huge thanks to Nez for building him the barrel and machining the muzzle brake to perfect timing. I cannot express enough how awesome he has been to help my son out.

The build is only phase 1 as he now has to earn more money to upgrade his trigger and stock. Basic M4 stock and milspec trigger aren't ideal, but he has the backbone of a great rifle.
 

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I'm a little late to the party, I built one this spring, used an Anderson lower and LaRue trigger, Strike industries lower parts. The upper was a Bear Creek that was a 556 upper, I ordered a barrel and bolt from Ballistic Advantage and changed them out.
I have been very happy with it so far using Hornady Precision Hunter ammo.
Picture of first group after zeroing so shots 4-6
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@ajvinyard just curious as to what muzzle brake that is on your nice-looking rifle.
thanks.
 
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