Ricochet - AbsoluteAstronomy.com

A ricochet is a rebound, bounce or skip off a surface, particularly in the case of a projectile

Projectile

A projectile is any object projected into space by the exertion of a force. Although a thrown baseball is technically a projectile too, the term more commonly refers to a weapon....

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

Variables

The likelihood of ricochet is dependent on many factors, including bullet shape, velocity (and distance), target material and the angle of incidence.

Bullet

Bullet construction has a major factor in determining both the likelihood of ricochet as well as where the bullet will travel afterward. Hard bullets have a greater tendency to penetrate than softer ones. Bullets that break up, such as varmint hunting bullets have a low risk of ricochet. The lower chance of ricochet is one of the reasons the newer .17 HMR

.17 HMR

.17 Hornady Magnum Rimfire, commonly known as the .17 HMR, is a rimfire rifle cartridge developed by the ammunition company Hornady in 2002. It descended from the .22 Magnum by necking down the .22 Magnum case to take a .17 caliber bullet, and it is more costly to shoot than traditional .22...

round with its frangible

Frangible

A material is said to be frangible if through deformation it tends to break up into fragments, rather than deforming plastically and retaining its cohesion as a single object...

bullet has gained popularity against the older non-fragmenting .22 WMR

.22 WMR

The .22 Winchester Magnum Rimfire, more commonly called .22 WMR, .22 Magnum, or simply .22 Mag, is a rimfire rifle cartridge...

Velocity

Ricochets are often more common with low-power calibers such as .22

.22 Long Rifle

The .22 Long Rifle rimfire cartridge is a long established variety of ammunition, and in terms of units sold is still by far the most common in the world today. The cartridge is often referred to simply as .22 LR and various rifles, pistols, revolvers, and even some smoothbore shotguns have...

or .177 calibre

.177 calibre

.177 caliber is the smallest size of pellets widely used in air guns, and is the only caliber generally accepted for formal target competition. It is also sometimes used for hunting small game, and in field target competition, where it competes with .20 caliber and .22 caliber rifles...

, which can have trouble penetrating some materials, although a ricochet can occur with any caliber. Higher velocity projectiles have a tendency to either penetrate the target, and/or to break-up on contact with it.

Target material

Bullets are more likely to ricochet off flat, hard surfaces such as concrete or steel, but a ricochet can occur on almost any surface, including grassy soil, given a flat enough angle of impact. Materials that are soft, give easily, or can absorb the impact, such as sand, have a lower incidence of ricochet. Though it may not be obvious, bullets easily ricochet off water; compare stone skipping

Stone skipping

Stone skipping is a pastime which involves throwing a stone with a flattened surface across a lake or other body of water in such a way that it bounces off the surface of the water. The object of the game is to see how many times a stone can be made to bounce before sinking.-Names:In North America...

Angle

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. Ricochets will almost always continue on a somewhat diagonal trajectory to their original trajectory, unless the impact is against a flat surface perpendicular to the angle of incidence (or approach), in which case the angle of reflection depends on the other variables involved.

Dangers

Ricochets are a common hazard of shooting because the bullet that ricochets poses a serious danger of causing collateral damage

Collateral damage

Collateral damage is damage to people or property that is unintended or incidental to the intended outcome. The phrase is prevalently used as an euphemism for civilian casualties of a military action.-Etymology:...

to animals, objects, or even the person who fired the shot.

In rare cases, ricochets can return to the shooter. This can occur when the object struck possesses enough resistance to withstand the impact of the bullet, and its surface is perpendicular to the shooter. Alternatively, elastic targets such as rubber tires shot with lower power weapons can return the slug along the line of fire even when struck at an oblique angle. Some bullets are designed to deform at the nose, which is the main reason for the bullet ricocheting at such an extreme angle and returning in the shooter's direction.

External links

"Ricochet Off Glass" at National Crime Investigation and Training web site
Video of fake Bullet Ricochet on Shooter
.50 Cal Ricochet onto Shooter's Ear Muffs - Youtube