Thats been my experience with only 4 cows out here...my "average" is 171 yds! ha I like 2x7, 3x9 etc but hunt on lowest usually, if not no more than 5X. I like that big field of vision they give. I shot a Black Wildebeest at 347 lasered yds in South Africa on 5x with my old 35 Whelen Ackley (200X) just fine, ha. I "did" get to kill one cow elk on 8X and another on 6X, other two was 5X and 4.5X. Love it!!