When firing a shotgun a sequence of events takes place what happens after you pull the trigger?

After you pull the trigger of a shotgun, the firing mechanism releases the firing pin, which strikes the primer of the shotgun shell. This ignites the gunpowder within the shell, creating a rapid expansion of gases that propel the shot or slug down the barrel. As the shot exits, it spreads in a pattern, depending on the choke and type of shell used. Finally, the shotgun then cycles to prepare for the next shot, if it is a semi-automatic or pump-action model.