LRH,
Ever considered doing a custom rig on one of the Lazzeroni cartridges www.lazzeroni.com?
Take a look at the ballistics for the 7.21 Firebird (284), the 7.82 Warbird (308), and the 8.59 Titan (338).
For instance, their 8.59 Titan holds ~10grs more water than the 338 Lapua.
Give them a...