8208 XBR?

[6arcgene]

Good evening fellas!!

I have been a 6.5 Grendel fan for years and I always used 8208 XBR powder in my reloads.

However, recently I have decided to convert all my small primer Grendel brass into 6 ARC and I am just about ready to start reloading some more 87 grain V-max bullets.

I know that I can get great velocities with CFE223. I obtained almost 3000 fps ( just shy of that ) with the CFE223 in a 20 inch barrel!!!

However, I still have 8 lbs of 8208 XBR left over that I would love to use with this new round!

So does anyone here have any experience with that powder in the 6 ARC? Have you obtained decent velocities... accuracy? Issues?

Just curious.

I will appreciate any feedback.

The Hornady manual does say that max charge velocity with the 8208 is around 2650 FPS; 

With the CFE223 its around 2800 fps... but like I said, I have chronographed mine up to around 2995 in a 20" Faxon barrel.

Anyway, thanks in advance for any constructive feedback!!!

Gene

[KMW1954]

I have not used that powder but, I would be inclined to think that if it worked very well in the Grendel it should work in the ARC. After-all they are basically the same just necked down.

[grayfox]

I, too, own and shoot both the grendel and 6 Arc, the Grrr for 8+ yrs and love the 8208 powder for 120 class. I save my 8208 for the grendel.
The powder-pressure response for the 6Arc is different than the grendel: with a smaller diameter bullet and barrel, pressure builds up more quickly and has smaller overall volume down the barrel. This is why 8208 is a kinda-fast powder type for the Arc.

6Arc typically needs slower powders for the similar weight bullet as compared to the 6.5 Grendel. You can push it too far in the 6 Arc.

The 6 Arc hornady data is for an 18" AR barrel, if you have a 20" then you will get about 75 fps more than the 18" listed.

You don't say what bullet you use in the grendel to get to 3000 ft/sec (6.5 does not have an 87 gr Vmax if I'm not mistaken), but in any case, you cannot simply extrapolate from grendel over to 6 Arc.

You also did not say what brand of 6.5 cases you are necking down. You are probably aware that one grendel case-mfr probably does not equal the volume in another mfr's case... so again, extrapolating straight over is not a good idea.

Best to start low and work up, noting for signs of overpressure - which liek grendel, if you have them you are already over 52 ksi limit. Stay within mfr data until you have a lot of experience and are willing to experiment a little. Both of these calibers achieve their results with moderate case pressures, they are not rifle-hot rods nor iron-clad magnums. Efficiency wins out over brute powder/force.

[6arcgene]

Thank you KMW1954

Grayfox, the almost 3000 fps were obtained with my 6 ARC using CFE223, 31 grains, in a 20 inch barrel, 87 grain V-Max bullet!!.
I never got such great velocities with the Grendel.

My brass is of various manufacturers but mostly Hornady: I understand that for reloading I should keep all my brass all the same brand, but I am not interested in "micro precision shooting"; If I hit my 18x18 metal plate at 400 yards, I am happy. I am not a competitor, just a casual plinker, hunter and (hopefully never) a home defender.

I downloaded a chart with all the various commercial powder burn rates. I am using it to cross reference with all powders I own to see if any of them might work in the 6 ARC. Like I said, I have lots of 8208 that I will no longer be using in the Grendel and just wanted to see if I can use it here.

I am also going to try BLC(2), Ramshot X terminator, TAC, and Varget. CFE 223 I know works very well and I love it. Just need other options as well.

I will let you all know what happens.

Thanks Grayfox!

[SpeyRod]

FWIW, I am loading the 87 vmax over Leverevolution and getting 2,940 out of a 20” Bartlien barrel gas gun. Accuracy has been excellent and I have shot ground squirrels out to 350yds with very high hit percentages. I found that my barrel liked LVR better than cfe223. Much more consistent.