By using the finite element method, the dynamic stress caused by vertical contact impact between bolt locking surface and barrel extension locking surface of a new rifle was studied.

采用有限元方法研究了某新型自动步枪枪机闭锁面与节套闭锁面间垂直接触碰撞的动应力。

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When these balls leave the barrel of a cannon or rifle they have an associated trajectory, velocity and so on and so forth.

当这些弹丸飞离炮管和枪管时刻，每一枚都会有了自己的弹道（抛物线）和不同的速率。

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The typical barrel of a high-power rifle has exterior grooves, called flutes, to reduce weight and create more surface area to enable the barrel to cool faster.

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They, too, found themselves staring down the barrel of an M4 rifle and being marched across to a holding area for potential prisoners.

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Another unique feature of the Delta Six is that by removing the barrel and collapsing the stock it converts from an assault rifle to a Sub Machine Gun.

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