Ricochet

A ricochet (/ˈrɪkəʃeɪ/ RIK-ə-shay; French: [ʁikɔʃɛ]) is a rebound, bounce, or skip off a surface, particularly in the case of a projectile.

The possibility of ricochet is one of the reasons for the common firearms safety rule "Never shoot a bullet at a flat, hard surface.

Alternatively, the same energy release may melt and/or disintegrate the bullet to reduce size and range of deflected particles.

Ricochets may be similarly deflected in the direction of rotation of the side of a spin-stabilized bullet contacting a resistant surface.

The angle of departure, both vertically and horizontally, is difficult to calculate or predict due to the many variables involved, not the least of which is the deformation of the bullet caused by its impact with the surface it strikes.

[10] In an extreme case, a strong, cohesive bullet striking a nearly perpendicular elastic surface may ricochet directly back at the shooter.

[11][12] This situation is sometimes observed when hardened armor-piercing bullet cores fail to completely penetrate steel plate.

The behavior of iron cannonballs documented during the era of muzzle-loading cannon may be a useful approximation for a BB gun or steel pellets fired from a shotgun, but inelastic collisions between the various shapes and materials of high-velocity bullets and the objects they may strike make bullet ricochets less predictable than the intuitive symmetry of low-velocity game spheres.

Lower initial mass gives small fragment ricochets less damage potential, and distance of travel is reduced by more rapid loss of velocity from air resistance.

Reduced ricochet range is one of the reasons the newer .17 HMR round with its frangible bullet has gained popularity against the older non-fragmenting .22 WMR.