Nemo
When you say BR, are you talking about a Rifle that will be used to go to the range with your friends, sit down, shoot some small groups, and have a good time?? We on this Forum refer to this as benchrest with a minor "b". It can be a very satisfying endevour, and the 6BR is certainly up to that task.
If you are talking about going to matches and competing,, particularilly at the Registered Match level, we refer to that as Benchrest with a Capitol "B".
There is a difference. You can build an extremely accurate Rifle in 6BR. The accuracy capability of the 6BR will amaze most shooters.
But, for competition, it does leave a little on the table when compared heads up with a 6PPC. That little bit is why you see very few 6BR's on the line at Matches, and multitudes of 6PPC's.
My advice to most shooters is for anything short of Benchrest Competition, (GROUP), go with the BR. But, if you really are serious about shooting Benchrest, especially the kind as represented on this Forum, go with a 6PPC.
Incidentally, if you do build a 6PPC, forget about all of that Sako Brass cr-p. 99 percent of all 6PPC Shooters use the LAPUA 220 Russian as the parent case. All you have to do is neck turn it, (if required in your chamber), and fireform it. It's no big deal. This simple operation is performed thousands of times each year by dedicated shooters all over the World.......jackie