What happens to a bullet shot straight up in the air? It does not go into space. Of course, it falls back to earth. The details, however, are interesting:
A bullet leaves the barrel of a gun at 2,000 – 3,000 feet per second. The bullet leaves the barrel nose first and spinning around its axis, which provides stability, due to the spiral grooves in the gun barrel.
When a bullet is fired 90 degrees to the horizontal the bullet is fighting the force of gravity and will gradually slow until it stops going up (at about 10,000 feet – or 2 miles) and then will fall back to the earth. If there were no air resistance, the bullet would return to earth going exactly the same speed as it left the gun barrel, i.e. around 2,500 feet per second. This is because gravity is a constant and gravity will cause the bullet to accelerate on the way down at the same rate as it slowed the bullet down on the way up.
However, on earth there is air resistance. As the bullet falls air resistance will cause the bullet to stop accelerating and hit terminal velocity (terminal velocity is the speed at which air resistance balances the accelerating force of gravity). Experiments have determined that falling bullets reach terminal velocity at 200-300 feet per second depending on type. Note that falling bullets (shot vertically) usually do not come down nose first – which would be the most aerodynamic – but instead tumble, which really slows the bullet.
When you fire a bullet into the air, it typically takes between 20 and 90 seconds for it to come down, depending on the angle it was fired at, its muzzle velocity and its caliber. So, if you are a bystander, you have some time to take cover.
A few questions this may raise and some answers:
- Can being hit with a bullet traveling 200-300 feet to second kill or injure you? Maybe. A bullet traveling at that speed might penetrate the skin depending on where it hits you. There are cases of people dying after being struck by falling bullets and other cases where there was only slight injury. But, most bullets shot up in the air are not shot exactly 90 degrees vertical and adding horizontal component to the firing of the bullet will increase the terminal velocity speed as a bullet shot at an acute angle maintains a ballistic trajectory and is not likely to engage in a tumbling motion. So, actual cases of injury or death might only be reflective of bullets fired at an angle other than 90 degrees to horizontal.
- What are the chances of the bullet that you shoot straight up coming back down and hitting you? Nearly zero. First, it’s very hard to shoot completely vertically. Second, wind will likely push the bullet far from the location where it was shot. Third, the spin of the earth will have a slight effect on where it will land compared to where it was shot.