A blank is a type of cartridge for a firearm that contains gunpowder but no bullet or shot. When fired, the blank makes a flash and an explosive sound (report). Blanks are often used for simulation (such as in historical reenactments, theatre and movie special effects), training, and for signaling (see starting pistol). Blank cartridges differ from dummy cartridges, which are used for training or function testing firearms; these contain no primer or gunpowder, and are inert.

Specialized blank cartridges are also used for their propellant force in fields as varied as construction, shooting sports, and fishing.

Applications

Blanks are commonly used when the sound and flash of gunfire is needed, but a projectile would not be safe, such as in military training maneuvers, in movies that require gun fights, and in starter's pistols to signal the beginning of races. Blanks used by the military are usually used with a special blank-firing adaptor in the firearm that constricts the barrel, keeping chamber pressures from the blank high enough and for long enough of a duration to cycle the firearm's action. For movie use, specially designed blank firing firearms are often used, which increases the margin of safety as they cannot be loaded with live ammunition. The 5-in-1 style of blank, designed to cycle through firearm actions and fit a variety of firearm chambers, is also commonly used in real firearms for dramatic effect. (The 5-in-1 is designed to function in .38-40 and .44-40 rifles and .38-40, .44-40 and .45 revolvers as used in Western movies.)

Special blank cartridges are also used for applications where the explosive power of a cartridge is needed, but a projectile is not. Blank cartridges were commonly used for launching rifle grenades, though some types of grenades are capable of trapping the bullet of a live round. Larger blanks are also used in line launching guns, such as the line launching kit for the Mossberg 500 shotgun.

Blank rimfire cartridges, commonly called power loads, are also used in some nail guns (powder-actuated tools), where the power is tapped to force a heavy piston into the nail, with enough force to bury its full length in steel or concrete.

Some forms of fast draw competitions use special blanks that are loaded with a layer of slow burning rifle powder on top of a thin layer of faster burning pistol powder. The pistol powder ignites the slower burning rifle powder, and fires it out the barrel much like a shotgun shell. The burning powder only travels a few yards before it completely combusts, but that is far enough to burst the balloon used as a target for those competitions. Wax bullets are also commonly used for competitions and training where a non-lethal projectile is required.

A blank cartridge may also be issued to a randomly selected shooter in an execution by firing squad, on the theory that each of the shooters may take comfort in the fact that they may not have fired a live round. This tradition dates back to before cartridge arms, when a muzzle loading musket would be loaded without a ball. However, it would, in fact, be obvious to the shooter of the blank round due to the lack of recoil.

Safety

The appearance of a blank cartridge is deceptively harmless and can give a false sense of safety. Although blank cartridges do not contain a bullet, precautions are still required because fatalities and severe injuries have resulted on occasions when blank cartridges have been fired at very close ranges. Also, cartridges loaded with wadcutter target bullets and cartridges for the Nagant revolver can be mistaken for blanks because the bullet does not protrude past the mouth of the cartridge casing.

Blank cartridges frequently contain a paper or plastic plug which seals the powder in the case called a wad. This wad can cause bruising at medium ranges and severe penetrating wounds at close range. There is also a cloud of hot, expanding gas which is expelled at extremely high velocity from the muzzle when a blank cartridge is fired. These high velocity gases can inflict severe injuries (see powerhead for an example) at close ranges. Additionally, if there is any small debris lodged inside the barrel it will be expelled at a similar velocity to a bullet, with the ability to inflict a severe wound. Finally, the extremely loud noise of blanks being fired can damage the hearing of people in the immediate area.

In general, such incidents occur when blank cartridges are fired by people who are unaware of their destructive capabilities. Actors in particular are at serious risk of injury from blank cartridges used on movie sets. Brandon Lee and Jon-Erik Hexum were both killed in accidents involving blank cartridges. Lee was killed because the gun had earlier experienced a squib load, in which a bullet had been left in the barrel, unknown to those on hand. It was propelled when the gun was loaded with blanks for the scene being shot. As reported in the investigation and court records, when Blank Ammo was loaded into the gun by someone other than the firearms expert the first shot was destined to fire the bullet out of the barrel. Hexum was killed when he placed a blank-loaded gun to his head and pulled the trigger—he did not realize the blanks had sufficient force to push the wad from the blank through his skull, sending bone fragments deep into his brain.

See also

• Coffman engine starter