Skeeter has it pretty much. Think of your bullet flying thru a tube. If the inside of the tube is 6", the bullet will never touch the top of the tube and max point blank will be reached when the bullet falls below the tube. The advantage I find is that I set my rifle's up to shoot particular size game and use that game's vital area, or close to it, as my target size. ie: I only use my 243 for shooting coyote's. So I have it set to hold dead on for as far as the bullet will never leave a 5" vital area. That mean's from line of sight, the bullet will never rise more than 2 1/2" above line of sight. For me that is a zero @ 236 yds and a point blank range@ 270 yds. That is the sure thing and at some point beyond 270 yds, you need to srart raising the sight's. If it's 10" top to bottom on a coyote's chest, I would only have to hold half the depth of the chest at 350 yds. Much beyond that and it's time to start a different program.

In the end, MPBR gives you all your cartridge has to give befor you have to srart figuring drop. At 400 yds, the load drop's 17.2". If I had a target type scope on it with turret's, I'd just dial in 17 click up and be 1/4" low. At 18 click's I would be 3/4" high. But befor you need to resort to that, use what the cartridge has to give you.

I have a 6.5x06 that I'm thinking of comp. shooting to 700 yds. In the game I'm concidering, the targets at each station range from 175 yds to 700 yds. The smallest target is an 8" steel plate and the largest a 14" steel plate. So to not have to worry about adjusting anything for a good way's, I sight the thing in to shoot at an 8" target at MPBR. Hold on the center of the 8" steel plate and if the wind doesn't do me, I have a hit out to somewhere around 300 yds. Haven't got my read out here now or I could give you the right ranges.