Re: 6mmBR loads
Using Fed205gm primers and Lapua brass, I found Benchmark made a good combo with Sierra 70 grain Blitzkings. My particular barrel was a 6ppc barrel with about 1300 rounds down it when I converted it to a short barreled 6br for varmints. The barrel is still smooth but it didn't like 70 grain ballistic tips or 75 grain Vmax. Only the blitzkings worked really well.
With Benchmark, I use the low end node of 32.5 grains because it shot a little better at 200 yards than the high node of 34.5 grains. Although the 32.5 grain load is kinda slow, it shoots great and still whaps the chucks well.
Also, my barrel is only 21" long so trying for super speed with it was kinda pointless.
6mmbr.com recommends using CCI br primers in the 6br and I couldn't see where it made any difference, except that my groups got bigger with them. Fed 205gm primers worked the best by far in every load I tried.
If it's not far, it's boring.