Many BB and pellet weapons are capable of shattering glass. Lower powered airguns have difficulties smashing tempered glass, however more powerful airguns can. Higher powerful BB guns have no issue taking on windows, and a fortuitous shot with a BB gun may sometimes smash a window. However, it is not usually enough to allow someone to enter your property. The most common way for a BB gun to break glass is by shooting straight up into the air. The force of the explosion against the glass causes it to shatter. If you shoot downward, the ball will bounce off rather than breaking the glass. You should never point your weapon at anything you do not intend to destroy. This includes people, buildings, and windows. If you do so, you could hurt someone unintentionally. Also, be sure to avoid firing into crowds or groups of people because you do not want to start a panic. In conclusion, a BB gun can break windows but it is not usually enough to allow someone to enter your property. It is important to keep track of your shots in case anyone needs medical help. Any moving part that could cause harm if turned too quickly should be locked out when not in use. And lastly, never fire into crowds or groups of people.