The premium bullet that your rifle likes best, shoots constant good groups with, and is available.
I would give my proverbial left nut to only use one bullet from my .222 to my .416, but the reality is that numerous have served me well and still do.
.222 - 45gr or 50gr TSX & 50gr V-max
.243 - 85gr TSX 87gr V-max
.250 Savage - 100gr A-frame
6,5x55 - 140gr NP, Rhino, A-frame
6,5x57 - 160gr Woodleigh PP
7x57FN - 160gr NP
7x57Brno - 175gr Hornady RN, 170gr Stewart Hi Performes
.308 -165gr Scirocco, 150gr Nosler BT
8x60 - 180gr TSX & 200gr NP
9,3x62 - 286gr Woodleigh, NP, Stewart Hi Performer
.375 Ruger - 250gr GMX, 300gr Woodleigh PP
.416 Ruger - 350gr A-frame, 400gr Woodleigh, 400gr Dzombo
.450-400 3&1/4” - 400gr Woodleigh,
400gr Dzombo
Note the V-maxes are used for culling or varminting