| 摘要 |
<p>The firearm has a barrel movable in relation to the casing, and a movable weight whose rear face forms the front wall of a variable-volume chamber. Gases tapped off propel the weight forward on firing, while force on the rear chamber wall locks the firing chamber to the breech during a first stage. In a second stage, the weight strikes a lug fixed to the barrel, opening the firing chamber to operate the fiream automatically. A second quantity of gas is tapped off to between the front face of the wieght and the lug, the space between them forming a second variable-volume chamber, reducing the speed of movement and avoiding damage due to striking the lug.</p> |
