It can be bad because the forged alloy in front of the hammer was not designed to take the force of a hammer hit. It is very possible to break the lower receiver buy pulling the trigger without a stop block in place or the assembled upper installed. Check the area in front of the hammer for damage.
NRA Chief Range Safety Officer, Home Firearm Safety and Basic Pistol Instructor
"There are three classes of people: those who see, those who see when they are shown, those who do not see."
Leonardo da Vinci