The 6 ARC rabbit hole, upper receiver input

[Sdvldog1371]

Well, Now I went and did it. I'm sure many of you are guilty of it. You want to buy or build a gun and you browse the web looking for deals, hem hawing, and never doing it because it doesn't make sense. Next thing you know you talked yourself into the first part, or a whole firearm.

Well, I was doing the theoretical assembly and cost for a precision 6mm ARC AR build. I already have a 6 ARC bolt action, brass, dies etc... Then I stumbled across what seems like a really good deal on a proof stainless 18" AR barrel. I violated the 1 rule of theoretical building...I left the browser tab open. Next thing you know, days later while cleaning up open tabs...I ended up buying the dang thing. So, Here I am, soon to be recipient of the barrel. I already have a fair idea of which bolt carrier group I will run. I have a floating lower, by floating I mean I have more than 1 upper and use that lower for for them.

My problem is this, I've never been big into AR's I refused to buy one until short stroke gas piston systems became available. I have farted around a little here and there with 300 blk and 5.56....meh. I have kind of gone away from them, but all of this recent posting about 6 ARC stuff got me thinking again.

I have a pistol length upper...I want to say Anderson? I was thinking of using that, then I thought, maybe I should go with an Aero Enhanced as a base, but I want built in ARCA and from what I can tell there aren't any built in ARCA hand guards that will work with their enhanced upper. Now I'm looking at billet matched upper and lower sets.

If I don't see tiny groups, this thing is getting hidden away like my other AR's in the back of the safe to hardly ever see use.

SO, to all of you builders of fully- semi- automatic AR-47s I call upon you...FIRST HAND EXPERIENCE ONLY. I want to build it super accurate, do I NEED matched upper and lower? Does anyone know of any ARCA hand guards that work with the Aero M4E1 enhanced upper?...I don't want to screw on a rail. Any Upper recommendations that would be a tight, if not thermo-fit with a proof barrel?

How about gas block and buffer recommendations?

Lastly, I'm looking to use an enhanced BCG, I have a couple candidates, but then the JP low mass popped up. Anyone have experience going from a standard to low mass in an ARC? Anyone know who makes the best fitting bolt for Proofs barrel extension?

Thanks Folks

 

[Hoss50]

My older son (12 currently) built 1 about 2 years ago. Awesome rifle, now I am looking for bolt guns in 6mm ARC.

We used an Aero Upper not the enhanced. We also built his lower, but it is M4e1.

A fellow member her was gracious enough to make him a barrel off a takeoff rifle he had. He is a match shooter, and made a very nice 18" barrel for my son. He recommended the Superlative Arms adjustable gas block, and i am glad he did. It works well, and now I have a few guns with them especially since I like to shoot suppressed.

We have not done a full load development on the barrel, but we have some handloads that shoot plenty well for my son to practice with and enjoy.

I personally would use a normal aero upper so you can have full access to any handguard you want, and buy a nice bolt and gasblock. It is such a cool round.

 

[cohunt]

Did you get a properly head spaced bolt with the barrel? If not, I'd suggest getting go/no go gauges to make sure it's right.

I've always lapped/trued the upper receiver face and use blue lock lite on the barrel extension to upper for a wiggle free fit when dry. Make sure you get a good trigger stay away from mil-spec triggers

As far as lightweight bcg and buffers--- I've used ti carriers and ultralight buffers ( as light as 1 oz) ,-- make sure you have an adjustable gas block ( I prefer non- bleed off, front click adj)

The lighter the carrier and buffer, the more pickey the gas block setting will be---, i have not had the cartridge you are looking at but have played with over 12 cartridges in AR's ( large and small frame)