I did use the 270 Win in an older Sako AV (PH's rifle) on my safari in South Africa in May. Using S&B ammo with 150 gr SP bullets, I took bontebok, red lechwe, and black and copper springbok. Worked just fine, with the shots ranging from 153-225 yards. (My wife was hunting black wildebeest and white blesbok with their LH Rem 700 in 308 Win, with another PH)
When I was chasing eland, I opted to use the Sako AV in 30-06 for a heavier, larger bullet (S&B 180 gr SP) for the significantly larger antelope. Never had a shot opportunity where we knew for certain that the animal we were looking at was the targeted old bull.
I have chosen to use 140 gr bullets in the 270 cal as a compromise for velocity and mass for penetration, for hunting, whether for the Win, WSM, or Wby. (But I have used 100 gr, 130 gr and 150 gr bullets too over the years.) Has worked well for me to date.