ISO 6mm ARC Lightweight AR15 Sub MOA

[tjend]

Looking for a 6mm ARC AR15 per the specs below. Mainly to be used for deer/hog/coyote, 1-300 yd shots, and long range plinking out to 600 yds.

16-18" Barrel
Shoot sub MOA @100yds
Sub 7LB weight empty no optic
Adjustable Gas Block for shooting suppressed

Anything out there direct from a manufacturer, or is building one the best way to go?

 

[StupidLightweight]

Building is the way to go. It ain't hard to assemble a 15. AR-10s are more difficult, but the 15 has been standardized for so long that it's straight plug-n-play. Holler if you have any questions.

 

[tjend]

I've built a couple AR's in the past, what components need to be 6mm ARC specific? Barrel, BCG and mag?

Building one seems to be the best option instead of spending 3k on a complete rifle that won't fully match what I'm looking for. Thanks @StupidLightweight

 

[StupidLightweight]

It's even easier. All you need is barrel, bolt (not carrier), and mag.

 

[tjend]

Perfect thanks, only other question I can think of is headspacing, should I buy a go/nogo gauge to confirm headspace on the upper/bolt and barrel chamber, or are design tolerances & part compatibility not as much of an issue nowadays. Thanks @StupidLightweight

 

[StupidLightweight]

I've never used go/no-go gauges for ARs. I suppose it could be an issue, but fired brass and loaded rounds is good enough for me.

 

[mother_plucker]

I've never used go/no-go gauges for ARs. I suppose it could be an issue, but fired brass and loaded rounds is good enough for me.

I'm right there with you. Never had to headspace an AR. I built an Aero P with a 18" Faxon barrel, and it is prob one of the most accurate rifles I have. It's really a great round, barely any recoil... Have just started to sight it in, and it made me want to have it in a bolt gun as well. Like @StupidLightweight said, a bolt for the 6.5 Grendel, mag and the 6 ARC barrel in any AR-15 will work!

 

[tjend]

Awesome, thank you both @mother_plucker @StupidLightweight

 

[RockAndSage]

OP, regarding lightweight guns and parts, you might take a look at V-Seven Weapon Systems. They're at the absolute top tier for lightweight precision and quality. With ARs and any guns really, if you don't want to sacrifice things like durability and accuracy when lightening things up, you're going to pay a lot more for the system. But V-Seven is at the top of the game. They also have a complete 16" 6 ARC that comes in right at 5 pounds:

16

(Item Code: 16LR ENLI 6MM FLT/16LR ENLI 6MM FLT-UR)V SEVEN Upper Parts:Enlightened 2055 Lithium-aluminum upper receiverMagnesium Hyper-Light 13.5” KeyMod or M-LOK handguard w/7068 alum. barrel nut (specify handguard type in comment box on order)16” 6MM Stainless Medium contour fluted barrel with...

www.vsevenweaponsystems.com

 

[chicoredneck]

What mags are you guys using for 6mm arc? The ones I have cause jams when I’m down to the last couple rounds in the magazine every time.

 

[mother_plucker]

I have had good luck with these two.

 

[Tobe_B]

A friend of mine just finished building one for me. I absolutely love it. It’ll be my main hunting rifle for all my big game. Nothing crazy or expensive, and I haven’t had much time to get it dialed in or break it in. But it’s shooting pretty decent so far, and it’s not too heavy. Weighs in around 9.5 lbs loaded.

Sent from my iPhone using Tapatalk

 

[Old-Cat]

Build it yourself https://www.thefreelibrary.com/The+...on+diameter+to+accuracy+in+the...-a0321900231

Barrel Bedding for the Precision AR15

Everyone has heard of bedding a bolt action rifle, but can you bed an AR15? Is it worth it. Yes and yes. Author Richard gives us the run down to enhance AR15 accuracy.

thenewrifleman.com

 

[tjend]

@RockAndSage those Vseven rifles look awesome but a little out of price range, budget is around 3k including optic, can probably build one around 6lb a little cheaper + optic weight.

@chicoredneck @mother_plucker for mags is was planning on getting a couple duramags https://dura-mag.com/duramag-ss-6-5-grendel-6mm-arc/

@Old-Cat awesome links, definitely lapping/bedding the receiver on this AR build.

Trying to find a Faxon Match Series Gunner 6mm ARC in 18" or might just do a proof carbon fiber 18" but they are a little pricey.

 

[RockAndSage]

@RockAndSage those Vseven rifles look awesome but a little out of price range, budget is around 3k including optic, can probably build one around 6lb a little cheaper + optic weight.

@chicoredneck @mother_plucker for mags is was planning on getting a couple duramags https://dura-mag.com/duramag-ss-6-5-grendel-6mm-arc/

@Old-Cat awesome links, definitely lapping/bedding the receiver on this AR build.

Trying to find a Faxon Match Series Gunner 6mm ARC in 18" or might just do a proof carbon fiber 18" but they are a little pricey.

You can build a killer gun for $3k, I think you're in good shape.

If I were in your position, I'd prioritize the parts of the build, decide what are non-negotiables and what doesn't matter as much, and go from there.

For me, non-negotiables are top-grade bolt, carrier, barrel, and trigger. You likely know a bunch of what I'll share below, but there might be some nuggets in here you or others might find helpful:

Bolt Carriers - The BCG is the heart of reliability (or death of it) in an AR, so it needs to come from a company that gauges every single part, properly stakes the gas key, and uses proper fasteners on the gas key. Forward Controls Design, Sons of Liberty Gun Works, and Modern Armory have pristine quality control on these points.

Bolt - For a 6 ARC, bolt reliability is even more important than in standard ARs, as the cartridge head size requires the bolt to have less material around the bolt face than a .223/5.56 bolt. They're known for shearing lugs and breaking extractors because of this. The best quality 6 ARC bolts I know of come from JP Rifles. It would be an extremely good idea to keep a spare extractor on hand as well.

Barrels - For barrels, your mentioning of Faxon and Proof are solid choices. I own a Proof-barreled ultralight AR, and love it. Keep in mind though that carbon-fiber barrels aren't necessarily lighter than a lightweight-profiled standard barrel, they're just lighter than a barrel of equal diameter. The advantage you get with them is that they're superbly stiff, and that's what I wanted for an ultralight build that I'd have a suppressor on (same thing if I ran a comp). Carbon barrels also seem to be more forgiving with handloading and finding a factory load that will shoot great...something about the construction seems to make the accuracy nodes bigger and easier to find.

Triggers - For triggers, this is much more personal choice, but having one that's reliable with an extremely crisp break is non-negotiable for me. One thing to know is that in the extremes, an open-design trigger is notably more reliable than a cassette style, as the cassette triggers seem to have a much harder time working when things like excess fouling from suppressors, popped primers, or grit get into them. As long as you know those limitations, they're great. I'd have zero hesitation running one in a hunting gun. For cassettes, I'm hearing extremely positive reviews of the Blackout Defense triggers, and for open designs, it's hard to beat Geissele, but I do hear LaRues can be a good value too.

Adjustable Gas Blocks/Gas Regulation Systems - Thumbs-up as well on running an adjustable gas block, especially for a build and in a somewhat uncommon caliber, if you want to tune for maximum reliability in cycling. Just know that if you expect to be able to tune it throughout the lifetime of the gun (different loads, etc), you need to regularly lubricate and rotate the screws with a penetrating oil in the adjustment mechanism, as they will seize up from fouling over time if you do not. The adjustable blocks from SLR Rifle Works are great choices. Up until recently I'd also have recommended you take a look at the adjustable/gas-regulated BCGs from 2A Armament, but they just got purchased by NEMO Arms, and their adjustable BCGs have disappeared from the market. I own two of these and I frankly wouldn't want to have to go without them. From what I can tell from the 2A/Nemo website they do expect to release a new/upgraded version of the regulated BCG, but for now, the adjustable 2A BCGs are almost impossible to find.

Mags - They can be so hit or miss with non-standard calibers, especially for builds. My best recommendation would be to buy 2 of each brand or capacity you're interested in, to the extent you can budget for it, and just see which ones run best. The ones guys mentioned above have good reputations, but also keep in mind that mags are consumable items, so plan on having spares. More often than not, they'll look just fine externally, but just start not functioning well at some point. Always number/mark your mags for this reason, so that you can ID and swap out a troublesome one quickly.

Everything else for me is a matter of preference, budget priority, and lately, availability. Depending on how high of a priority accuracy is for you, very stiff handguards and tight-tolerance uppers and lowers can be very helpful. Don't go cheap on those, but you'll get fine performance out of a lot of offerings.

 

[tjend]

Awesome, thanks @RockAndSage, do you see any issues doing an Aero upper, lower, handguard on this build or are there better options for receivers. I'd prefer those three components match/from same manufacturer.

 

[General RE LEE]

Had a Bushmaster 5.56 sitting in safe and decided to get a 6 ARC Upper. I bought a complete upper from Grendel Hunter and found a pretty good hunting handload. 20 shot group with 108 grain ELDMs.

 

[mother_plucker]

@RockAndSage those Vseven rifles look awesome but a little out of price range, budget is around 3k including optic, can probably build one around 6lb a little cheaper + optic weight.

@chicoredneck @mother_plucker for mags is was planning on getting a couple duramags https://dura-mag.com/duramag-ss-6-5-grendel-6mm-arc/

@Old-Cat awesome links, definitely lapping/bedding the receiver on this AR build.

Trying to find a Faxon Match Series Gunner 6mm ARC in 18" or might just do a proof carbon fiber 18" but they are a little pricey.

I've built quite a few rifles including my 6 arc on Aero receiver sets. think for the money, they are great!

 

[RockAndSage]

Awesome, thanks @RockAndSage, do you see any issues doing an Aero upper, lower, handguard on this build or are there better options for receivers. I'd prefer those three components match/from same manufacturer.

I'd second what @mother_plucker said, Aero is great for the money, and are a solid choice. I don't think you'd go wrong in going that direction, especially if it helps you put money into a great optic, barrel/bcg, etc.

You did ask if there are "better options" - think of Aero as a really solid Tacoma. You're not going to go wrong with that choice. But there's always Raptors, Dodge TRXs, etc out there too. AR "builder sets" (upper, lower, handguard) from V-Seven, Seekins, SLR Rifleworks, or Blackout Defense are some of the top of the line for quality and performance, but there's also a point of diminishing returns, as with any high-performance equipment. After a certain level of capability, doubling the cost does not get you double the performance.

That said, if you want to ensure reasonable precision and reliability, I wouldn't go much cheaper than Aero, either. Small variances in either the upper or lower can and do cause problems with accuracy, reliability, and even trigger pull. Aero's excellent value, but below that in cost you generally see a lot more quality problems.

On that note, you'll enhance your build a great deal on an Aero builder set - in terms of accuracy - by doing what @Old-Cat offered in that article, in truing up your upper and bedding/shimming the barrel.

If you don't mind, share build photos later on once you get going on it, it would be fun to see.

 

[mother_plucker]

Just a build I did with an Aero receiver set, Smoke Composites stock and grip with a Brigand Arms carbon handguard. Gas block, takedown pins, firing pin, BCG and everything I could get in titanium was done, Faxon pencil barrel (wanted a Proof but thought I’d spent enough) and a drop in trigger with the Trijicon MRO. Weighs in at 4.7lbs without the silencer. I should weigh my 6ARC build to compare…
Sky's the limit on what you can do with your own AR build!
Would enjoy seeing pictures when you get it done!!