Using one caliber for whitetail hunting is like wearing one set of clothes, or eating the same food over and over. Ive killed deer with, from smallest to largest:

.223
.243
.257 Roberts
6.5x55
.30/30
.30/06
7.62x54R
8x57
.38/40
.444 Marlin
.45/70
577/450
.45, 50, and .54 roundball.
Why limit yourself?