Mick,
To streamline the process, and of course to save a coins for NitroExpress.com, I'll limit my testing to the following:
256
7x57 (275 Rigby)
275 H&H Mag
280 Ross
30-06
300 H&H
300 Weatherby
303 British
8x57
318 WR
333 Jeff
338 Win
350 Rigby Mag
9.3x62
9x57
375 H&H

As you will notice, Mick, no Remington cartridges!!!

Should I include the 45/70 Govt (in a Marlin lever action of course). Oh yeah, that's just for Dangerous Game.