The distance a bullet can travel in water varies significantly based on several factors, including the type of bullet, its velocity, and the water's density. Generally, studies indicate that bullets travel much shorter distances in water compared to air due to the increased resistance posed by the water's density.
Most bullets lose their energy quickly upon entering water. For instance, common handgun rounds typically travel only a few feet before coming to a stop. For example, a 9mm bullet might only go about 2 to 3 feet before it loses enough momentum to sink. In contrast, high-velocity rifle bullets, such as those from a .223 Remington or a .308 Winchester, could potentially travel up to about 10 to 15 feet, but they also lose their velocity rapidly.
The physics behind this rapid deceleration can be attributed to the density of water, which is about 800 times denser than air. As a bullet enters the water, it encounters significant drag, which slows it down much more effectively than in air. Moreover, water's incompressibility means that when a bullet strikes the surface, it does not push the medium away as it would in air, absorbing the energy much more efficiently.
It's also important to consider the bullet's construction. A full metal jacket (FMJ) bullet is likely to retain its shape better under water compared to hollow-point or soft-tip bullets, which are designed to expand and might break apart, further influencing how far they can travel.
In summary, while a bullet can travel several feet in water, it is significantly less than what it can achieve in air. Notably, concerns about safety and the unpredictability of bullets in water make it essential to handle firearms responsibly and with attention to the environment around you.