This is terminal velocity. That velocity can and does still kill people from stray gun fire by idiots.
No, not terminal velocity. It has been shown that the energy is not enough to do that. Seen referred to as about the same amount of energy that a brick has dropped from 4 feet. Generally that is retained muzzle velocity, as the gun was not fired straight up, but at an angle where it never slows all the way down to terminal velocity.
The falling bullet: myths, legends and terminal velocity | Forensic Outreach
So What Happens to All Those Bullets Fired in the Air? Can They Kill You? | TheBlaze.com
Celebratory gunfire - Wikipedia, the free encyclopedia
The greater the angle away from vertical, the greater chance of it retaining increasing energy levels to cause damage.