Either cartridge will work fine as long as you shoot it well. Antelope aren't hard to kill.
I've killed 4 over the years; two with a bow, and two with a rifle. Two two with my bow were each around 20 yards. One shot with my 7mm mag was at ~100 yards, running wide open, and the other was at 212 yards, standing broadside, looking away from me.
In open country, use low ground to stalk them.
Daryl