自动步枪都是利用枪机的往复运动完成推弹进膛和退壳,如果采用能开启的弹膛,就无需枪机的往复运动,直接将枪弹横着推进弹膛,闭合弹膛后就能发射。这与转轮枪有点类似,不同的是弹膛只有一个,且是能开合的(如图1)。为了实现自动射击,需要一个导气机构完成开膛、退壳、进弹、闲膛等动作,类似导气式自动步枪。 Automatic rifles are the use of the reciprocating motion of the bolt to complete the projectile into the bore and back shell, if the opening can be used without the reciprocating movement of the bolt, the projectile directly bullet projectile, after the closure of the chamber can launch . This is a bit similar to the revolver, except that the only one chamber, and is able to open and close (Figure 1). In order to achieve automatic firing, you need a gas guide mechanism to complete the opening, back-shell, into the bomb, free bombs and other movements, similar to gas-guided automatic rifles.