Semiautomatic Pistols

Semiautomatic pistols were developed in the early 1900s. As mentioned, the cartridges are stored in a magazine in the grip of the pistol. When a shooter readies this type of weapon, he or she will pull back the slide, which is located at the top of the frame of the pistol, and release it. As the slide moves forward, it picks up the cartridge at the top of the magazine and slides it into the firing chamber. At this point, the hammer is placed in the firing position. When the shooter pulls the trigger, the hammer strikes the firing pin, setting off the cartridge. The bul- let travels down the barrel of the gun, propelled by the expanding hot gases from the burning of the propellant. At this time, a second action is taking place, the opposite and equal action to propelling the bullet down the barrel of the gun. Remember, the hot gases try to expand in all directions. The firing chamber prevents them from expanding to the sides. Since the slide of the gun is movable, while the bullet is being forced through the barrel, equal and opposite action will force the slide backward. As the slide goes back, the just-fired cartridge casing is ejected from the firearm through the ejection port, and the hammer is cocked. The slide reaches its farthest distance back, comes forward, picks up another cartridge at the top of the magazine and slides it into the firing chamber. The pistol is again ready to fire. When the shooter pulls the trigger, the process repeats.