Powerhead
Encyclopedia
A powerhead, bang stick, or shark stick is a specialized firearm
used underwater that is fired when in direct contact with the target. Powerheads are often used for spear fishing, and against shark
s or alligator
s for sport, defense, or to kill nuisance animals. The term powerhead refers to the firearm-like part of the device; when attached to a shaft to form a spear
, it may be referred to as a bang stick or shark stick. The spear in question may be handheld, or launchable from a spear gun.
for the cartridge, a firing pin to fire the cartridge, and usually some form of safety pin or latch that prevents firing when it is engaged. The rear of the power head is fitted with some provision for attaching to a spear.
Powerheads are available that chamber a variety of handgun
, rifle
, and shotgun
cartridges, from .22 WMR
to 12 gauge
and larger. .357 Magnum
is probably the most common, as it is fairly powerful yet still compact enough to be used in a spear gun. Large cartridges such as the 12 gauge are generally only used on a handheld spear.
Some powerheads use the cartridge to propel a barbed spear point into the target. These are generally used on a bangstick used for alligator hunting, to secure a line to the alligator to prevent escape.
s are generally designed to work in air, which has a very low density
. The density of water
is roughly 1000 times higher than that of air at sea level, and that reduces the penetration of a bullet proportionally. A bullet might travel a mile (1.6 km) in air, but travel no more than a few feet (about a meter) in water. Expanding hunting or defensive ammunition, such as that using hollow point bullet
s, will penetrate even less, as the water is dense enough to cause the bullet to expand. By firing while in contact with the target, a powerhead does not waste energy on traveling through the water, but rather expends all its energy directly on the target.
ammunition
, such as .357 Magnum
or .44 Magnum
, the bullet has little or no effect on the killing power of the bang stick. The muzzle blast
does the damage, as much high-pressure gas is forced into the flesh of the target. Blank cartridges
can produce fatal wounds when fired in or near contact, and they work well in powerheads. One commercially produced version used a modified .30-30 Winchester
cartridge case, loaded backwards, with a primed .38 Special
cased loaded in its mouth holding the primer. The cartridge was loaded with the .30-30 case facing outwards, so that the .30-30 case full of burning powder was propelled into the target upon firing.
or varnish
is commonly used around the primer and case mouth. For shotshells, a layer of rubber
, such as a balloon, can be used to seal the crimped front of the shell.
Note that this ruling is with regard to the National Firearms Act
, and not to the 1968 Gun Control Act. (The National Firearms Act defines 'firearm' as machine gun
s, short barreled rifles, short barreled shotguns
, and concealable firearms that are neither pistols nor revolvers.) This means that powerheads may still be under the authority of the 1968 Gun Control Act with regards to shipping them and purchase of them from licenced dealers.
Laws may also prohibit the use of powerheads in sport fishing. They are allowed in US federally controlled waters, but many states prohibit their use in state controlled waters.
Firearm
A firearm is a weapon that launches one, or many, projectile at high velocity through confined burning of a propellant. This subsonic burning process is technically known as deflagration, as opposed to supersonic combustion known as a detonation. In older firearms, the propellant was typically...
used underwater that is fired when in direct contact with the target. Powerheads are often used for spear fishing, and against shark
Shark
Sharks are a type of fish with a full cartilaginous skeleton and a highly streamlined body. The earliest known sharks date from more than 420 million years ago....
s or alligator
Alligator
An alligator is a crocodilian in the genus Alligator of the family Alligatoridae. There are two extant alligator species: the American alligator and the Chinese alligator ....
s for sport, defense, or to kill nuisance animals. The term powerhead refers to the firearm-like part of the device; when attached to a shaft to form a spear
Spear
A spear is a pole weapon consisting of a shaft, usually of wood, with a pointed head.The head may be simply the sharpened end of the shaft itself, as is the case with bamboo spears, or it may be made of a more durable material fastened to the shaft, such as flint, obsidian, iron, steel or...
, it may be referred to as a bang stick or shark stick. The spear in question may be handheld, or launchable from a spear gun.
Design
A powerhead consists of a long length of tubing which is the chamberChamber (weaponry)
In firearms, the chamber is that portion of the barrel or firing cylinder in which the cartridge is inserted prior to being fired. Rifles and pistols generally have a single chamber in their barrels, while revolvers have multiple chambers in their cylinders and no chamber in their barrel...
for the cartridge, a firing pin to fire the cartridge, and usually some form of safety pin or latch that prevents firing when it is engaged. The rear of the power head is fitted with some provision for attaching to a spear.
Powerheads are available that chamber a variety of handgun
Handgun
A handgun is a firearm designed to be held and operated by one hand. This characteristic differentiates handguns as a general class of firearms from long guns such as rifles and shotguns ....
, rifle
Rifle
A rifle is a firearm designed to be fired from the shoulder, with a barrel that has a helical groove or pattern of grooves cut into the barrel walls. The raised areas of the rifling are called "lands," which make contact with the projectile , imparting spin around an axis corresponding to the...
, and shotgun
Shotgun
A shotgun is a firearm that is usually designed to be fired from the shoulder, which uses the energy of a fixed shell to fire a number of small spherical pellets called shot, or a solid projectile called a slug...
cartridges, from .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...
to 12 gauge
Gauge (bore diameter)
The gauge of a firearm is a unit of measurement used to express the diameter of the barrel. Gauge is determined from the weight of a solid sphere of lead that will fit the bore of the firearm, and is expressed as the multiplicative inverse of the sphere's weight as a fraction of a pound . Thus...
and larger. .357 Magnum
.357 Magnum
The .357 S&W Magnum , or simply .357 Magnum, is a revolver cartridge created by Elmer Keith, Phillip B. Sharpe, Colonel D. B. Wesson of firearms manufacturer Smith & Wesson, and Winchester. It is based upon Smith & Wesson's earlier .38 Special cartridge. The .357 Magnum cartridge was introduced in...
is probably the most common, as it is fairly powerful yet still compact enough to be used in a spear gun. Large cartridges such as the 12 gauge are generally only used on a handheld spear.
Some powerheads use the cartridge to propel a barbed spear point into the target. These are generally used on a bangstick used for alligator hunting, to secure a line to the alligator to prevent escape.
Purpose of contact-shooting
BulletBullet
A bullet is a projectile propelled by a firearm, sling, or air gun. Bullets do not normally contain explosives, but damage the intended target by impact and penetration...
s are generally designed to work in air, which has a very low density
Density
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight...
. The density of water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
is roughly 1000 times higher than that of air at sea level, and that reduces the penetration of a bullet proportionally. A bullet might travel a mile (1.6 km) in air, but travel no more than a few feet (about a meter) in water. Expanding hunting or defensive ammunition, such as that using hollow point bullet
Hollow point bullet
A hollow point is an expanding bullet that has a pit or hollowed out shape in its tip, generally intended to cause the bullet to thin upon entering a target in order to decrease penetration and disrupt more tissue as it travels through the target. It is also used for controlled penetration, where...
s, will penetrate even less, as the water is dense enough to cause the bullet to expand. By firing while in contact with the target, a powerhead does not waste energy on traveling through the water, but rather expends all its energy directly on the target.
How they work
Although most commercial powerheads use standard handgunHandgun
A handgun is a firearm designed to be held and operated by one hand. This characteristic differentiates handguns as a general class of firearms from long guns such as rifles and shotguns ....
ammunition
Ammunition
Ammunition is a generic term derived from the French language la munition which embraced all material used for war , but which in time came to refer specifically to gunpowder and artillery. The collective term for all types of ammunition is munitions...
, such as .357 Magnum
.357 Magnum
The .357 S&W Magnum , or simply .357 Magnum, is a revolver cartridge created by Elmer Keith, Phillip B. Sharpe, Colonel D. B. Wesson of firearms manufacturer Smith & Wesson, and Winchester. It is based upon Smith & Wesson's earlier .38 Special cartridge. The .357 Magnum cartridge was introduced in...
or .44 Magnum
.44 Magnum
The .44 Remington Magnum, or simply .44 Magnum, is a large-bore cartridge originally designed for revolvers. After introduction, it was quickly adopted for carbines and rifles...
, the bullet has little or no effect on the killing power of the bang stick. The muzzle blast
Muzzle flash
Muzzle blast is the term used to describe the release of high temperature, high pressure gases expelled from the muzzle of a firearm when it is discharged. Muzzle flash is the term used to describe the visible light of the muzzle blast. The blast and flash are caused by the combustion products of...
does the damage, as much high-pressure gas is forced into the flesh of the target. Blank cartridges
Blank (cartridge)
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 . Blanks are often used for simulation , training, and for signaling...
can produce fatal wounds when fired in or near contact, and they work well in powerheads. One commercially produced version used a modified .30-30 Winchester
.30-30 Winchester
The .30-30 Winchester/.30 Winchester Center Fire/7.62×51mmR cartridge was first marketed in early 1895 for the Winchester Model 1894 lever-action rifle. The .30-30 , as it is most commonly known, was the USA's first small-bore, sporting rifle cartridge designed for smokeless powder. The .30-30 is...
cartridge case, loaded backwards, with a primed .38 Special
.38 Special
The .38 Smith & Wesson Special is a rimmed, centerfire cartridge designed by Smith & Wesson. It is most commonly used in revolvers, although some semi-automatic pistols and carbines also use this round...
cased loaded in its mouth holding the primer. The cartridge was loaded with the .30-30 case facing outwards, so that the .30-30 case full of burning powder was propelled into the target upon firing.
Ammunition issues
Since most powerheads are designed to use commercial ammunition, which is not designed to be used underwater, the ammunition used must be waterproofed. A coating of nail polishNail polish
Nail polish, or nail varnish, is a lacquer applied to human fingernails or toenails to decorate and/or protect the nail plate.-History:...
or varnish
Varnish
Varnish is a transparent, hard, protective finish or film primarily used in wood finishing but also for other materials. Varnish is traditionally a combination of a drying oil, a resin, and a thinner or solvent. Varnish finishes are usually glossy but may be designed to produce satin or semi-gloss...
is commonly used around the primer and case mouth. For shotshells, a layer of rubber
Rubber
Natural rubber, also called India rubber or caoutchouc, is an elastomer that was originally derived from latex, a milky colloid produced by some plants. The plants would be ‘tapped’, that is, an incision made into the bark of the tree and the sticky, milk colored latex sap collected and refined...
, such as a balloon, can be used to seal the crimped front of the shell.
Legal issues
A powerhead may be considered a firearm under some circumstances. In the US, the BATFE considers a powerhead a firearm if it is not permanently affixed to a shaft; generally powerheads are sold spot welded to a temporary steel shaft giving an overall length of greater than 18 inches (45 cm). After installing permanently on a spear shaft, the spot weld is cut, and the temporary shaft discarded.-
- Revenue Ruling 55-569, C.B. 1955-2, 483 says:-
- "A device ostensibly designed for submarine spear fishing, but capable of chambering and firing .22 caliber rimfire ammunition, is a firearm within the purview of the National Firearms Act. However, such device, if permanently attached to the speargun shaft by the manufacturer, would not be a firearm."
Note that this ruling is with regard to the National Firearms Act
National Firearms Act
The National Firearms Act , 73rd Congress, Sess. 2, ch. 757, , enacted on June 26, 1934, currently codified as amended as , is an Act of Congress that, in general, imposes a statutory excise tax on the manufacture and transfer of certain firearms and mandates the registration of those firearms. The...
, and not to the 1968 Gun Control Act. (The National Firearms Act defines 'firearm' as machine gun
Machine gun
A machine gun is a fully automatic mounted or portable firearm, usually designed to fire rounds in quick succession from an ammunition belt or large-capacity magazine, typically at a rate of several hundred rounds per minute....
s, short barreled rifles, short barreled shotguns
Sawed-off shotgun
A sawed-off shotgun also called a sawn-off shotgun and a short-barreled shotgun , is a type of shotgun with a shorter gun barrel and often a shorter or absent stock....
, and concealable firearms that are neither pistols nor revolvers.) This means that powerheads may still be under the authority of the 1968 Gun Control Act with regards to shipping them and purchase of them from licenced dealers.
Laws may also prohibit the use of powerheads in sport fishing. They are allowed in US federally controlled waters, but many states prohibit their use in state controlled waters.
External links
- Wally Gibbins with an eleven foot tiger shark and 10 gauge shotgun powerhead in 1963.
- Powerhead detonation on a shark.