6MM ARC Load Data

[Eric H]

Dialed in my 6MM ARC after stepping away from LeveRevolution and going with Varget.

 

[Eric H]

Is anyone making 6ARC Brass?

 

[Dmagna]

Varget works well. Lever and cfe 223 are too temp sensitive, no brass as of yet. I have tried to form brass from 6.5 and it seems it loves to develop a belt. Hopefully someone will make better brass.

 

[Dmagna]

I just went from an 18" proof to a 20" and a new bolt so I am starting over with load development today. I had good luck with 108 eldm and varget. 1/2" groups at 100 yards just shy of 2500 fps out of an 18"

 

[Eric H]

I first reformed 6.5Grendel then just used brass from Hornady manufactured brass.

 

[GLTaylor]

Eric,
Need twist, primer, bbl length please.
Thanks

 

[Eric H]

7.5, CCI450, 24 inch

 

[bubbaonpc]

Just starting an ARC build on AR. Thinking 18" bbl...I see members using 20", 22", and 24". I'm wanting accuracy. Mnts of NC don't allow for 1k long shots. Any advice from y'all's experience or a recommended thread ? Thank you

 

[Eric H]

Just starting an ARC build on AR. Thinking 18" bbl...I see members using 20", 22", and 24". I'm wanting accuracy. Mnts of NC don't allow for 1k long shots. Any advice from y'all's experience or a recommended thread ? Thank you

Haven't tried on an AR but I know the loads are quite different than the Bolt gun.

 

[Dmagna]

Just starting an ARC build on AR. Thinking 18" bbl...I see members using 20", 22", and 24". I'm wanting accuracy. Mnts of NC don't allow for 1k long shots. Any advice from y'all's experience or a recommended thread ? Thank you

I am seeing no speed difference in 18" to 20" barrels. Seems the factory match doesn't speed up much in any barrel length. Seems to be rigor around 2500-2600 depending on temp.

 

[AKGuide]

17FEB2021 34F, 99%H, 29.85inhg
Virgin Starline 1.480", Rem 7 1/2, [email protected], 107 [email protected]" CBTO for 0.010" jump
2721avg, sd5; 0.85" w/ magneto attached
0.84" without but 1.2" low and 1.08" left

This was my most consistent load in my AR it has a 26" McGowan 1:7" 0.089" gas port barrel, Odinworks adjustable gas block, JP BCG. I have now run out of cfe223 and will be working up a load using a2520 to see if I can match accuracy.

Reuben

 

[backwoods83]

I have 3 6 ARCs, one I wouldn't mind selling, but that's a different story. Anyway, my first, a custom AR, wears a 26" 7.5 twist CBI from Compass Lake, it has a rifle plus 2 gas system and a Superlative Arms adjustable gas block, also 5.7ozs of buffer weights. I use Starline 6.5 Grendel brass reformed, I simply run it through the AMP, run it through the FL die with no guts, trim, run back through the FL die with the guts. 3 firings thus far, no bulging or belts, 30grns Leverevolution, CCI 450s, 105gr Berger vlds, 2.280", 2906fps. I haven't had an issue with the brass or the powder acting crazy with temperature changes. The other 2 I have are bolt actions, 1 18" Savage, the other a 27" Preferred Barrel Blanks prefit on a Ruger American. In those, I fireformed Lapua 220 Russian brass into 6ARC, trim .010" neck up to 6mm, load a mild charge, seat a bullet .015" in the lands, and send it. Fireforming loads are typically sub moa. The 18" Savage shoots the exact same load as the AR, except with Lapua brass, the Ruger American shoots 29.7grns of Leverevolution under 108 Berger Elite hunters. CFE223, Leverevolution, PP2000MR, AA2520, offer the best velocity and are scary accurate. Varget is stable and mostly accurate, velocity really sucks and it pressures up quick, ok in a bolt, not so much in an AR. H4895 is better for stability and velocity, also pressures up too quick in an AR. The formed Lapua 220 Russian brass has the same capacity as formed Starline Grendel brass, both have more capacity (.5grns h2o more) than Hornady ARC brass, and both are stronger. You can also use Lapua 6.5 Grendel and form it. The best tradeoff for powders that offer decent stability with awesome velocity, PP2000MR is your answer. It takes some tinkering and experimenting, but it's a fun little cartridge, and is pretty stout and extremely accurate. Imr 4895, 4166, 4064, AA2230, AA2460, BLC2, W748, AA2495, Ramshot Tac, Ramshot Exterminator, N140, N540, RL15, Norma 203B are also decent choices, depending on the application. RL17 is actually quite accurate in this cartridge as well, does good for mild loads, but you run out of capacity before getting the high node.

 

[8x68s]

A lot of good info here! Thank you, gentlemen!!