FWIW, i have a 280 rem with the same problem... 160's print twice as large as 175's... so i shoot 175's since i like throwing as much lead downrange as i can... my 280 will also accurately throw 140's and 150's... but for some odd reason not 160's... i've loaded about 10 different powders behind them a whole matrix of other tweaks...

use the 175's... you won't have any issue...

Jamie