As some of the earliest had straight rather than spiral grooves, it is thought the purpose may have been to receive the powder residue or fouling that was a problem with early firearms.

他们当中最早的一些是直膛线而不是螺旋膛线。人们认为这样便于回收未燃烧的火药或是火药残渣。因为在当时火药的回收还是个问题。

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As some of the earliest had straight rather than spiral grooves, it is thought the purpose may have been to receive the powder residue or fouling that was a problem with early firearms.

他们当中最早的一些是直膛线而不是螺旋膛线。人们认为这样便于回收未燃烧的火药或是火药残渣。因为在当时火药的回收还是个问题。

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