6mmARC Military Application

[Jerry M.]

time to do away with the standard mag well configuration.. Just my thought.. Jerry.

[MISportsman]

I just don't understand why the arc and not the grendel itself??? In my opinion it is much more suited for the job!

[LRRPF52]

I just don't understand why the arc and not the grendel itself??? In my opinion it is much more suited for the job!

Flatter trajectory very similar to 6.5 Creedmoor, lower recoil.

You can get the same felt recoil with a Grendel if you shoot 107gr SMK/TMK compared to the 105-108gr 6mm bullets, but the 6mm 105gr+ class of bullets have much higher BCs.

6mm 108gr ELD-M is .536 G1 BC/.270 G7

6.5mm 107gr TMK is .445 G1

6.5mm 107gr SMK is .406-.420 G1

You get higher hit probability and better sight picture stability during the shot when shooting the lighter weights with higher BCs.

Cartridge stack in the magazine is easier for the spring to lift with lighter weight bullets as well, and easier to carry loaded mags for the soldier.

[LRRPF52]

If you listen to that Hornady podcast/interview with the engineers that developed 6mm ARC, they mentioned that they started out with 12” and longer 6.5 Grendel barrels for the DoD customers.

The "DoD entities” were facing the problem of insurgents and combatants who would sit outside of their 5.56 NATO carbine engagement distances, so they started using more SR-25s and 7.62 NATO rifles to solve that problem, but it gave them all sorts of other problems we’ve talked about for years, namely weight, limited ammo, CQB restrictions/overpressure in the house, lack of maneuverability, etc.

They set up a number of different shooting scenarios to mimic real-world distances and problems, but gave them various length 6.5 Grendel AR-15s instead.

After working through all these field and urban shooting scenarios, they asked all the personnel what they would choose to carry, the SR-25/7.62 NATO weapons, or 6.5 Grendel AR-15s.

Without exception, all the guys said they would pick the 6.5 Grendels, 12”-18”, depending on what they were doing.

Hornady felt they could improve it with some “tweaks”, and necked it down to 6mm, which had already been done since Grendel brass was made available in the mid 2000s (6mm AR).

That reduced weight even more, reduced muzzle climb, flattened the trajectory, maintained a nice limited wind drift, and maintained supersonic reach out to considerable distances.

That was the whole impetus behind 6mm ARC.

[video=youtube_share;GtZUxn2Je-8]https://youtu.be/GtZUxn2Je-8[/video]

[danm]

Great synopsis! I jumped in early-ish when Grendel came out and for a while was probably the only one in my area shooting it. When 6ARC was announced I again jumped in fairly early, not to replace my Grendels but just to add to my diversity of arms. I lucked out too on ammo, after ordering some 105s and 108s online I was at my local Sportsman's and they had 30 boxes of 108s on the shelf and they had just lifted their purchasing limit.... bought em all for 22$ a box!!! Currently have an 18" and 14.5" ARC both with PROOF cf barrels and my good old 18" and 11.5" Grendels..... (plus a 16" and 14.5" 5.56) Not huge but it's a well rounded stable

[BluntForceTrauma]

Dang, son, good score on all that ammo!

[danm]

Dang, son, good score on all that ammo!

Yeah
I couldn't believe it....
And, I don't feel bad either since I'm pretty sure I was one of the first adopters in my area...
I didn't here any rumors of Seekins 6ARC offering till well after I had my 18" built

[BlogSarge]

Speaking of ammo, Mile High has the ELD-X for $32/box. The -X is the cheapest load right now. I stocked up. I think I’ll take it pig hunting this fall!

[Old Bob]

Today I made a tour of the local gun shops looking for Grendel & 6mm ARC goodies. Zilch, zip, nada for any thing Grendel related. I did find some of those new Hornady 6mm 80gr CX bullets (Sportsmans Warehouse). When I asked store employees when they might get things like bullets, brass, powders & primers suitable for Grendel or 6 ARC, I got a lot of shoulder shrugs. Most stores here keep their primers & powder in their back rooms instead of on the shelves. They'll have lists of those items on a counter where you can see what they have in stock. I didn't see anything on those lists that were usable for me. There were some powders but they were mostly for magnum calibers, shotguns & pistols. There were small bunches of large rifle, small pistol & shotgun primers as well. Every store I went to had s**t loads of .223 Rem & 5.56 NATO, 308 Win & 7.62 NATO, 9mm Lugar & 7.62x39 ammo. Some stores had enough of those items they could support their own armies.

[LRRPF52]

I saw 6mm ARC Hornady Match White Box maybe last year in the summer at Smith & Edwards in West Jordan, UT.

Haven’t seen any since. Grendel I can find both at LGS and online.

Military contracts for 6mm ARC will take precedence over civilian sales, and the size of the contracts are very small in comparison to everything else going on.

Would have been cool for them to figure this out in the 1950s and mate the AR-15 with a true rifleman’s/DM cartridge, but sometimes it takes 60+ years for things to happen.

[BlogSarge]

Anyone seen any credible info on what the military load is?

Right now I can get any of the civilian loads and the LE load from Mile High and have stocked up enough to last a few months. But still I wonder what the mil uses. The police TAP load reportedly does well in the FBI tests, but the precision is poor. The ELD-X load is right now the cheapest and is an expanding, sub MOA load. I just bought another case!

[Fess]

I get the impression that the military load is different from current civilian loads. In their podcasts, if I recall correctly, the Hornady guys mentioned that the 110 grain A-Tip is based on the military bullet shape and is different from the ELD's. They mentioned that Hornady has a special group that works on law enforcement and military projects

[VASCAR2]

I can’t remember where I read it but I I read the new military 6 ARC used the EPR (Enhanced Performance Round “green bullet”) of similar design to the 5.56 M 855-A1.

[danm]

I can’t remember where I read it but I I read the new military 6 ARC used the EPR (Enhanced Performance Round “green bullet”) of similar design to the 5.56 M 855-A1.

That's exactly what I was thinking

[BluntForceTrauma]

Piecing together offhand comments from Hornady, Geissele, and Military Arms Channel, etc., in which those comments corroborate each other, I consider it confirmed that the SEALs requested 6mmARC and are testing it.

Haven't heard about a specific "military" load, though, (besides Hornady's 6mmARC 106gr TAP) and I wouldn't expect one until some sort of formal adoption. Pretty sure it'd be a 6mm EPR M855A1 analog, as V2 mentioned, if it is ever adopted.

[BlogSarge]

Piecing together offhand comments from Hornady, Geissele, and Military Arms Channel, etc., in which those comments corroborate each other, I consider it confirmed that the SEALs requested 6mmARC and are testing it.

Haven't heard about a specific "military" load, though, (besides Hornady's 6mmARC 106gr TAP) and I wouldn't expect one until some sort of formal adoption. Pretty sure it'd be a 6mm EPR M855A1 analog, as V2 mentioned, if it is ever adopted.

You both are probably spot on about the EPR load being most likely.

I wondered about the TAP load, but it is an expanding bullet and I think that is disallowed, as is the plastic tip maybe.