The structure of the crushing gun is similar to that of a revolver, but it is simpler and has a lower risk factor. A revolver is a small pistol. Generally, there are 5-6 bomb nests in the runner, up to 10 bomb nests. Bullets are installed in bullet holes and can be fired one by one. In order to match the habit of most people using their right hands, the wheel is often placed on the left, so it is often called "left wheel" in Chinese. In fact, the original name means "revolver", which has nothing to do with left and right. The runner design of revolver pistol is earlier than the flintlock era 17 18. 1835, American colt improved the previous design and obtained patents from Britain and the United States. Unlike all other firearms, the barrel and bore of a revolver are separate.