a metal block in breech-loading firearms that is withdrawn to insert a cartridge and replaced to close the breech before firing
例句
The stiffness and strength of Breechblock must meet the design requirements. 闩体的刚度和强度必须满足设计要求。
Xingwen produces wood breechblock, wall nail, single line nail, broad nail, spear nail, thick wall nail and etc. 我厂生产的产品主要有：木螺丝，干壁钉，单线钉，墙板钉，自攻钉和粗牙干壁钉等产 品。
The locking system features a linearly moving bolt (breechblock) with a separate tilting locking piece. 锁定系统以一个倾斜锁定块的分开以线感人的门闩 (闩体尾栓) 为特色。
Because the equivalent stress is invariable when the pressure goes down,the breechblock opening time does not affect forces for extraction. 因此抽壳力是必要的，而且开栓时间对抽壳力的影响很小。
The breechblock (bolt) is located under the bolt carrier, and the locking piece is hinged to the bolt and located under it. 闩体尾栓 (门闩) 位于门闩运送者之下，而且锁定块被装铰链到门闩而且位于在它之下。
Obturation Pattern Analysis of High Pressure Wedge Breechblock 高膛压楔式炮闩闭气形式分析
