【上期回眸】本文第二、三部分介绍了M1914系列步枪弹的种类、结构、主要特征等。随着时代的发展进步,该弹已显落伍,于是又在弹头种类、被甲材料以及弹壳形状等方面加以变化,形成了本文介绍的M1939系列步枪弹。鉴于该系列步枪弹涉及的弹种较多,故分两部分进行介绍。 [Review] The second and third parts of this article introduced the type, structure and main features of M1914 series rifle shells. With the progress of the times, the bomb has been obviously out of date, so it was changed in the type of warhead, the material of the armor and the shape of the cartridge shell to form the M1939 series rifle cartridge introduced in this article. In view of the series of rifles involved in bullet more, so divided into two parts to introduce.