Greg,
Simple answer here; then you'd have 280 or 6,5-06 brass. Nothing magical here, just straight-forward case reforming. As with any reforming operation, you'll have to watch (that means check, and double check) your neck wall thickness, the possible development of donuts, case length after reforming . . . the usual stuff. I'd recommend using an intermediate step (at least one) for the 6,5-06, that is, necking them to 280, and then again down to 6.5. As a general rule, I prefer to neck up, rather than down. The vast majority of my own 6,5-06 cases were reformed from 25-06 brass, simply necking it up a few thou. The Lapua cases are definately a higher quality than the 25-06 cases I used as parents/donors, but hey, I was on a much tighter budget at that time.