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Point-blank range is any distance over which the trajectory of a given projectile fired from a given weapon remains sufficiently flat that one can strike a target by firing at it directly. Point-blank range will vary by a weapon's external ballistics characteristics and target chosen. A weapon with a flatter trajectory will permit a longer maximum point-blank range for a given target size, while a larger target will allow a longer point-blank range for a given weapon.〔(【引用サイトリンク】title=Definition for "point blank range" )〕 In forensics and popular usage, point-blank range has come to mean extremely close "can't miss" range with a firearm, within four feet of its muzzle at moment of discharge yet not close enough to be a contact shot.〔 ==History== The term ''point-blank range'' is of French origin, deriving from ''pointé à blanc'', "pointed at the target", with the word ''blanc'' used to describe a small white aiming spot formerly at the center of shooting targets. Today, point-blank range denotes the distance a marksman can expect to fire a specific weapon and hit a desired target without adjusting its fixed sights. If a weapon is sighted correctly and ammunition reliable, the same spot should be hit every time at point-blank range. The term originated with the techniques used to aim muzzle-loading cannon. Their barrels tapered from muzzle to breech, so that when the top of the cannon was held horizontal its bore actually sat at an elevated angle. During firing, recoil caused the gun's muzzle to elevate slightly, resulting in an upward movement of the shot. This caused the projectile to rise above the natural line of sight shortly after leaving the muzzle, then drop below it after the apex of its slightly parabolic trajectory was reached. By repeatedly firing a given projectile with the same charge, the point where the shot fell below the bottom of the bore could be measured. This distance was considered the ''point-blank range'': any target within it required the gun to be depressed; any beyond it required elevation, up to the ''angle of greatest range'' at somewhat before 45 degrees.〔 Various cannon of the 19th century had point-blank ranges from 250 yards (12 lb howitzer, powder charge) to nearly 1075 yards (30 lb carronade, solid shot, powder charge).〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Point-blank range」の詳細全文を読む スポンサード リンク
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