range drop

Point-blank range is any distance over which a certain firearm can hit a target without the need to compensate for bullet drop, and can be adjusted over a wide range of distances by sighting in the firearm. If the bullet leaves the barrel parallel to the sight, the bullet, like any object in flight, is pulled downwards by gravity, so for distant targets, the shooter must point the firearm above the target to compensate. But if the target is close enough, bullet drop will be negligible so the shooter can aim the gun straight at the target. If the sights are set so that the barrel has a small upward tilt, the bullet starts by rising and later drops. This results in a weapon that hits too high for very close targets, too low for very far targets, and point blank at some distance in between.
Point-blank range will vary by a weapon's external ballistics characteristics and the allowable error at the target; the flatter the bullet's trajectory or the larger the target, the longer the point-blank range will be.In popular usage, point-blank range has come to mean extremely close range with a firearm, yet not close enough to be a contact shot.

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