How does a semi auto pistol work?

Answer 1

Firing pin strikes the primer of the cartridge, causing it to fire. The flame from the primer ignites gunpowder, which burns rapidly. Gasses created by burning powder push bullet down barrel, a the same time pushing back on the slide of the pistol. Since the slide is heavier than the bullet, it moves much slower. As the slide is pushed back on it's springs, it pulls the fired cartridge case from the chamber, and it is flipped out of the pistol (ejection). At the end of the stroke, springs that were compressed during recoil now push the slide forward, stripping fresh cartridge from magazine, and sliding it into the chamber. You are now ready for the next shot.