http://en.wikipedia.org/wiki/Ballistic_coefficient
this why we need to pay attention to the B.C.
a quote from wikipedia
A bullet with a high BC will travel farther than one with a low BC because it is affected less by air resistance, and retains more of its initial velocity as it flies downrange from the muzzle (see external ballistics).[10]
When hunting with a rifle, a higher BC is desirable for several reasons. A higher BC results in a flatter trajectory for a given distance, which in turn reduces the effect of errors in estimating the distance to the target. This is particularly important when attempting a clean hit on the vital organs of a game animal. If the target animal is closer than estimated, then the bullet will hit higher than expected. Conversely, if the animal is further than estimated the bullet will hit lower than expected. Such a difference from the point of aim can often make the difference between a clean kill and a wounded animal.
This difference in trajectories becomes more critical at longer ranges. For some cartridges, the difference in two bullet designs fired from the same rifle can result in a difference between the two of over 30 centimetres (12 in) at 500 metres (550 yd). The difference in impact energy can also be great because kinetic energy depends on the square of the velocity. A bullet with a high BC arrives at the target faster and with more energy than one with a low BC.
Since the higher BC bullet gets to the target faster, there is also less time for it to be affected by any crosswind.
Ghost
this why we need to pay attention to the B.C.
a quote from wikipedia
A bullet with a high BC will travel farther than one with a low BC because it is affected less by air resistance, and retains more of its initial velocity as it flies downrange from the muzzle (see external ballistics).[10]
When hunting with a rifle, a higher BC is desirable for several reasons. A higher BC results in a flatter trajectory for a given distance, which in turn reduces the effect of errors in estimating the distance to the target. This is particularly important when attempting a clean hit on the vital organs of a game animal. If the target animal is closer than estimated, then the bullet will hit higher than expected. Conversely, if the animal is further than estimated the bullet will hit lower than expected. Such a difference from the point of aim can often make the difference between a clean kill and a wounded animal.
This difference in trajectories becomes more critical at longer ranges. For some cartridges, the difference in two bullet designs fired from the same rifle can result in a difference between the two of over 30 centimetres (12 in) at 500 metres (550 yd). The difference in impact energy can also be great because kinetic energy depends on the square of the velocity. A bullet with a high BC arrives at the target faster and with more energy than one with a low BC.
Since the higher BC bullet gets to the target faster, there is also less time for it to be affected by any crosswind.
Ghost