Easiest might be the MBPR method.... no adjustment in field, no holdover within range just point and shoot provided your within the range.
Choose your accepted target size hit zone, depending on size it might be 2 4 or 6inches for example. Then use a spreadsheet or online calculator to work out the ZERO distance where the bullet path does not go greater than half the target size above or below (rise or fall in trajectory) the point of aim as it travels from the muzzle to the target.
Using the example of a 308win with a 168gr proj of BC 0.45 (the variables here are muzzle vel and BC only!)
Into the spreadsheet we get;
Zero distance 228yds (first zero at 24yds) .
This translates to a max rise of 3inches at about 130yds
and a drop of 3inches at about 267yds
This means that the projectile, velocity, zero combination provides a Maximum point blank range of 267yds. What this means is that provided you are able to determine/estimate that the range is at or less than 267yds - put the crosshair dead-on and you will be within the 6inch range (+3/-3) on the target whether the actual distance is 20 or 150 or 267yds.....