要把针头的利角及磨纹磨走，我们会利用滚筒型的砂轮把针头磨成尖、圆、平或子弹形形状。

To get rid of the sharp Angle and the grinding tracks on the probe, the tip will be polished by roll-typed grinding wheels to become sharp, round, flat or ball pointed.

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弹头（在枪膛中）的前进过程中，铁制子弹（此处指底座上的铁质闭锁，也有使用软木制作闭锁的——译注）会膨胀，紧咬住螺旋形的膛线，使得射程和精准度都大大增加，同时减少子弹死火。

On its way, the iron bullet expanded, gripping the spiral rifling and spinning so tightly along its course that its range and accuracy were greatly increased, with fewer misfires.

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