Powders and Bullets

[Stonegables]

At this time, 6mm ARC was launched 2+ years ago. As I just got a 20" gas gun (1:7.85) and have a few once fired brass with reloading hardware, CFE223 and Hornady 105 HPBT on the way, which powers are working best in gas guns with which bullets? I am primarily interested in shooting groups at 1000 yards. Therefore the powders that give the highest velocities with the lowest SD and ES with 105-108 bullets within gas gun pressures at what I am looking for. Is CFE223 the best? Does Hornady's relatively inexpensive 105 HPBT bullet have the fight stuff?

[grayfox]

There are a couple on here who have gone out to 1000, I have not. I've gone 300 yds.
But the 105 factory... maybe. At least it gives you some brass.
the 108 factory ought to be in there also.
Some of it depends on what you can find.
Some barrels will need some break in, maybe 50-100 rounds and then they tend to speed up about 50 fps or so.
For the heavies, look at Hornady's data for gas guns, it's a pdf on here as well as on line.
Lever will give you about ~100 fps more MV per grain than CFE, but both seem to be good, also the 2520.
Now all 3 are ball powders so they will have some temp issues as it gets really hot/cold from your loading temp.

Berger has some 105's and 109's available, hornady has their stuff as well, 105/108. Or the sierra 107 SMK hpbt... kind of depends on what your barrel will like.

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The hornady 105 loads shorter than saami, usually around 2.200 or a bit less, check it in your barrel before you load a bunch of them. The vld's, like 108, 109 107's, can load longer, mag length will be your limit for those more than likely.

[CZ527 Guy]

My observations has been CFE 223 & Leverevolution offer top velocities with the heavy bullets & do great when temps are stable . If you need more temp stable powder Varget is what you are looking for. Good luck finding Varget if you want it. Keep in mind Varget will give up a bit of velocity over LVR & CFE 223.

[trianglevelvet]

LVR and 107gr Sierra match kings will get you up around 2650-2700 fps, which will easily get you out to 1000 yards at pretty much any altitude.

Temp stable powders will get you up to maybe 2600-2625fps. StaBall 6.5 can do that.

[GRH]

With 105's Varget works better in the upper charge weight range. Below 25.5gr the burn drops below 90%.

Right now I'm working with A2520[attachment=535]