Cartridge----------------Bullet weight gr ---------Muzzle velocity------Muzzle energy
.338 Lapua Magnum ----- 250 -----------------2970 (905.2)-----4893 (6634.0)[4]
.338 Lapua Magnum ---- 300 -----------------2717 (828.1)-----4919 (6669.2) [5]
.408 Chey Tac ----- 305 -----------------3500 (1066.8)----8298 (11250.5) [6]
.408 Chey Tac ----- 419 -----------------3000 (914.4)------8376 (11356.3) [7]
.416 Barrett ----- 400 -----------------3250 (990.6)-----9380 (12717.5)
.50 BMG ----- 700 -----------------2978 (907.7)-----13971 (18942.1)
I have alot of land 10km to shoot on
You need a 338 or a 300 RUM, a mil dot scope lots of practice and tracers to shoot that far. Keep in mind tracers are FMJ and therefore not legal for hunting.
Theoretically, the furthest bullet will have the highest BC launched at the same velocity.
So in Canada, the most common readily available bullet to do this is the 338 300gr MK at 3000fps. Wildcat bullets is making some very high BC bullets in alot of different cals so you can explore those.