Actually I was thinking the 260 imp 30 degree. I thought it had a longer neck than it does. I think it will have a little more oomph than the 6.5 super LR, which in its own right is pretty sweet as well.
Ideally, a 6.5x47L and a 284 shehane would be sweet, but I prefer the idea of one gun and learning how to use it. 6.5 or 7mm for 300-1000yds? Well 7mm is the flavour of the month, but I think the above cartridge might perform quite well. Especially would like to neck down 308 palma brass and see how it would work.