I decided that I would completely abandon all 6mms and shoot 6bra. Across the board. My first 6bra is a Brux 7.5 with the Alex Wheeler 104 fb chamber but my reamer is a 272 neck. Then I have my varmint rifle with a Rock Creek 8 twist same chamber. Waiting for my 12 twist Bartlein barrel for my short range action. Lt32 is great so far for light bullets but I'm going to test ar comp and if it continues to perform I am just going to shoot that for a while in all weights. I am so tired of chasing temp changes and Alliant powders are my favorites.
We have done the same thing, both of our 6mm benchrest guns are 6bra’s and also getting a 6bra barrel for my varmint rig. Really like how accurate they are even while fireforming and how consistent the brass turns out.
For us it surely was, we will have brass that is retired from benchrest that’s still great for varmiting(I am not a serious varmint guy) and playing on steel. Win win!
My new 7.5 Brux 6bra barrel with Alex Wheeler 104 reamer and 272 neck. Fireforming with 80 Bergers and AR Comp. 31 to 32.5 grains. 32 grains was single digit spreads right at 3250. Only varied a few fps total and many were the same velocity exactly. Ar comp is impressive.
I’m kinda liking 8208 right now. It’s what Bart S recommended for me to try with his 80 Gr Boat Tail Dominators. It’s giving me some 5 shot groups in the 2s with single digit SDs and 3310 average FPS at 32.7 grains. I think I will load some more at 32.6 and play with the seating depth a little.
How the throat is set up will be your limiting factor more so than the twist. The 1:8 will be fine with light bullets unless it’s throated for 105s, then you will be jumping then too far for best accuracy.
8208 appears to be closer to lt32. Ar comp is a bit slower. I'm still shooting fire forming loads. I have not recieved my 12 twist barrel yet. But it will be the same chamber.
