I have shot African game (Kudu x3) in excess of 200 yards with my 25" barrelled 9.3x62 and 286 Woodleigh PPSN's. You will find that projectile profile will have more effect at 9.3 velocitys than minor gains or loss in velocity due to barrel length.

I have found the 250 Nosler Accubond can be driven flat enough for effective use out to 300 yards and will try to use some on Camels in June.

For ranges less than 100 yards I would use a Woodleigh Bonded 286 RNSP or conventional Lapua 285 RNSP on small soft skinned game for maximum expansion and 'thump'.