I am seriously considering rebarreling to a 6.5 rem mag. The link to ReloadersNest will show that there is no information on that caliber. They do have some loads listed for it though.
The best place to get diagrams of the actual case dimensions is Ricciardelli's webpage at http://stevespages.com/page8d.htm
. There is not a lot of info out there but it should be a helluva caliber and it is the only 6.5 that will fit my bolt.
You can still get Remington brass. There are dies but I will have to have a Lee Collet made for it or possibly use the 6.5x55 Swede Collet die and Lee Factory Crimp. Redding will make a Body Die and RCBS says I can use one of their Competition Seaters in a 6.5x55 Swede.
Let us know what you decide.