Striations or contours on a fired bullet that run parallel or approximately parallel to the axis of the bullet. There are several possible types of axial engravings, including, but not limited to marks left by or due to: 1) the mouth of the cartridge case; 2) the chamber throat; 3) irregularities or burrs along the forward edge of a chamber in a revolver cylinder; 4) inconsistent rotation of a bullet as it moves down the bore; 5) misalignment of a revolver chamber with the axis of the bore (also known as forcing cone marks, misalignment marks, or out-of-time marks); and 6) the rifling, prior to engagement with and rotation of the bullet (also known as slippage marks, skid marks, or jump marks).
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