Powerhead (firearm)

Last updated
Powerhead (firearm)
TypeUnderwater Firearm
Specifications
Cartridge

A powerhead 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 sharks or alligators 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. [1] [2] [3]

Contents

Design

A powerhead consists of a length of tubing which is the chamber 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. [1]

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. [1]

Some powerheads use the cartridge to propel a barbed spear point into the target. These are generally used on a bangstick for alligator hunting, to secure a line to the alligator to prevent escape. [2] [4]

Purpose of contact-shooting

Bullets are generally designed to work in air, which has a very low density. The density of water is roughly 800 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 bullets, 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. [1]

How they work

Although most commercial powerheads use standard handgun ammunition, such as .357 Magnum or .44 Magnum, many users choose to use larger caliber ammunition to do maximum damage to the intended target. [ citation needed ] A common misconception of how powerheads function is that the muzzle blast does the damage, as much high-pressure gas is forced into the flesh of the target. While the gas does do some minimal damage, it is ultimately the penetration of the slug that causes the damage to the target. Most powerheads function just as traditional firearms do, except that it is the spear which acts as the firing hammer. One commercially produced version used a modified .30-30 Winchester cartridge case, loaded backwards, with a primed .38 Special case 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. [1] [5] This system is fast to reload and one of the most effective despite the fact that it does not use a bullet.

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 polish 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. [1] [2]

Australia

In Australia they are classed as category A firearms requiring a legitimate reason for issuance of a permit to acquire to a weapons licence holder. When not in use, they must be safely stored in a locked container with ammunition stored separately. Regulations vary between states, with some states permitting their use for defense against sharks only, and not for spearfishing.

United States

A powerhead may be considered a firearm under some circumstances. In the US, the ATF 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. [3] 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.

Revenue Ruling 55-569, C.B. 1955-2, 483

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 guns, 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 regard to shipping them and purchase of them from licensed dealers. [3]

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. One can be easily in violation of state law despite being compliant with federal regulations.

Related Research Articles

<span class="mw-page-title-main">Firearm</span> Gun for an individual

A firearm is any type of gun that uses an explosive charge and is designed to be readily carried and used by an individual. The term is legally defined further in different countries.

Handloading, or reloading, is the practice of making firearm cartridges by assembling the individual components, rather than purchasing mass-assembled, factory-loaded ammunition.

<span class="mw-page-title-main">Shotgun</span> Firearm intended for firing a junta of small to medium-sized pellets

A shotgun is a long-barreled firearm designed to shoot a straight-walled cartridge known as a shotshell, which discharges numerous small spherical projectiles called shot, or a single solid projectile called a slug. Shotguns are most commonly used as smoothbore firearms, meaning that their gun barrels have no rifling on the inner wall, but rifled barrels for shooting sabot slugs are also available.

<span class="mw-page-title-main">Cartridge (firearms)</span> Ammunition consisting of a casing, projectile, propellant, and primer

A cartridge, also known as a round, is a type of pre-assembled firearm ammunition packaging a projectile, a propellant substance and an ignition device (primer) within a metallic, paper, or plastic case that is precisely made to fit within the barrel chamber of a breechloading gun, for convenient transportation and handling during shooting. Although in popular usage the term "bullet" is often used to refer to a complete cartridge, the correct usage only refers to the projectile.

<span class="mw-page-title-main">.357 Magnum</span> Revolver cartridge

The .357 Smith & Wesson Magnum, .357 S&W Magnum, .357 Magnum, or 9×33mmR is a smokeless powder cartridge with a 0.357 in (9.07 mm) bullet diameter. It was created by Elmer Keith, Phillip B. Sharpe, and Douglas B. Wesson of firearm manufacturers Smith & Wesson and Winchester. The .357 Magnum cartridge is notable for its highly effective terminal ballistics.

<span class="mw-page-title-main">Rimfire ammunition</span> Type of ammunition common in low-caliber firearms

Rimfire ammunition (RF) is a type of firearm metallic cartridge whose primer is located within a hollow circumferential rim protruding from the base of its casing. When fired, the gun's firing pin will strike and crush the rim against the edge of the barrel breech, sparking the primer compound within the rim, and in turn ignite the propellant within the case. Invented in 1845, by Louis-Nicolas Flobert, the first rimfire metallic cartridge was the .22 BB Cap cartridge, which consisted of a percussion cap with a bullet attached to the top. While many other different cartridge priming methods have been tried since the mid-19th century onwards, such as pinfire, only small caliber rimfire and centerfire cartridges have survived to the present day with regular usage. The .22 Long Rifle rimfire cartridge, introduced in 1887, is by far the most common ammunition in the world today in terms of units sold.

<span class="mw-page-title-main">Blank (cartridge)</span> Firearms filler device that produces an explosion but does not fire a projectile

A blank is a firearm cartridge that, when fired, does not shoot a projectile like a bullet or pellet, but generates a muzzle flash and an explosive sound like a normal gunshot would. Firearms may need to be modified to allow a blank to cycle the action, and the shooter experiences less recoil with a blank than with a live round. Blanks are often used in prop guns for shooting simulations that have no need for ballistic results, but still demand light and sound effects, such as in historical reenactments, special effects for theatre, movie and television productions, combat training, for signaling, and cowboy mounted shooting. Specialised blank cartridges are also used for their propellant force in fields as varied as construction, shooting sports, and fishing and general recreation.

<span class="mw-page-title-main">Shotgun shell</span> Self-contained cartridge loaded with either shot or a solid slug

A shotgun shell, shotshell, or shell is a type of rimmed, cylindrical (straight-walled) cartridges used specifically in shotguns, and is typically loaded with numerous small, pellet-like spherical sub-projectiles called shot, fired through a smoothbore barrel with a tapered constriction at the muzzle to regulate the extent of scattering. A shell can sometimes also contain only a single large solid projectile known as a slug. The hull usually consists of a paper or plastic tube often covered at the base by a metallic head cover which retains a primer, and the shot charge is typically contained by a wadding/sabot inside the case. The caliber of the shotshell is known as its gauge.

<span class="mw-page-title-main">.22 Winchester Magnum Rimfire</span> Rimfire cartridge

The .22 Winchester Magnum Rimfire, also called .22 WMR, .22 Magnum, .22 WMRF, .22 MRF, or .22 Mag, is a rimfire cartridge. Originally loaded with a bullet weight of 40 grains (2.6 g) delivering velocities in the 2,000 feet per second (610 m/s) range from a rifle barrel, .22 WMR is now loaded with bullet weights ranging from 50 grains (3.2 g) at 1,530 feet per second (470 m/s) to 30 grains (1.9 g) at 2,200 feet per second (670 m/s).

<span class="mw-page-title-main">Riot gun</span> Type of firearm

In current usage, a riot gun or less-lethal launcher is a type of firearm used to fire "non-lethal" or "less-lethal" ammunition for the purpose of suppressing riots or apprehending suspects with minimal harm or risk. Less-lethal launchers may be special purpose firearms designed for riot control use, or standard firearms, usually shotguns and grenade launchers, adapted for riot control use with appropriate ammunition. The ammunition is most commonly found in 12 gauge shotguns and 37mm or 40 mm grenade launchers.

Obturation is the necessary barrel blockage or fit in a firearm or airgun created by a deformed soft projectile. A bullet or pellet made of soft material and often with a concave base will flare under the heat and pressure of firing, filling the bore and engaging the barrel's rifling. The mechanism by which an undersized soft-metal projectile enlarges to fill the barrel is, for hollow-base bullets, expansion from gas pressure within the base cavity and, for solid-base bullets, "upsetting"—the combined shortening and thickening that occurs when a malleable metal object is struck forcibly at one end.

<span class="mw-page-title-main">Express (weaponry)</span> Term applicable to hunting rifles and ammunition

The term express was first applied to hunting rifles and ammunition beginning in the mid-19th century, to indicate a rifle or ammunition capable of higher than typical velocities. The early express cartridges used a heavy charge of black powder to propel a lightweight, often hollow point bullet, at high velocities to maximize point blank range. Later the express cartridges were loaded with nitrocellulose-based gunpowder, leading to the Nitro Express cartridges, the first of which was the .450 Nitro Express.

A rim is an external flange that is machined, cast, molded, stamped, or pressed around the bottom of a firearms cartridge. Thus, rimmed cartridges are sometimes called "flanged" cartridges. Almost all cartridges feature an extractor or headspacing rim, in spite of the fact that some cartridges are known as "rimless cartridges". The rim may serve a number of purposes, including providing a lip for the extractor to engage, and sometimes serving to headspace the cartridge.

<span class="mw-page-title-main">20-gauge shotgun</span> Smoothbore shotgun chambering

The 20 gauge shotgun, also known as 20 bore, is a type of smoothbore shotgun. 20 gauge shotguns fire a shell with a diameter of .615 in (15.6 mm), while the 12 gauge shell has a diameter of .729 in (18.5 mm). 12 gauge and 20 gauge shotguns are the most popular gauges in the United States. The 20 gauge is popular among upland game hunters, target shooters, and skeet shooters.

<span class="mw-page-title-main">Caliber conversion sleeve</span> Device used to allow a firearm to fire a different cartridge

A caliber conversion sleeve or adapter sleeve is a device which can be used to non-permanently alter a firearm to allow it to fire a different cartridge than the one it was originally designed to fire. The different cartridge must be smaller in some dimensions than the original design cartridge, and since smaller cartridges are usually cheaper, the device allows less expensive fire practice.

<span class="mw-page-title-main">Snake shot</span> Handgun and rifle cartridge loaded with lead shot

Snake shot, rat shot or dust shot, more formally known as shotshell or canister shot by technicality, refers to handgun and rifle cartridges loaded with lead shot canisters instead of bullets, intended for pest control. As the names suggest, the main targets for such ammunition are serpents, rodents, birds and other pests at very close range.

<span class="mw-page-title-main">Hunting weapon</span> Weapon primarily for hunting game animals

Hunting weapons are weapons designed or used primarily for hunting game animals for food or sport, as distinct from defensive weapons or weapons used primarily in warfare.

<span class="mw-page-title-main">Super magnum</span> Type of firearm cartridge

A super magnum is a longer and/or more powerful version of a "magnum" cartridge. Although the term "super magnum" typically refers to a handgun cartridge, created by lengthening an existing straight-case design, it can also refer to rifle and shotgun cartridges, such as the .17 Winchester Super Magnum and the 312" 12 Gauge Super Magnum. In this case, it simply denotes that it is of greater power than existing "magnums" of a similar caliber or gauge, this is comparable to other designations, such as the "Remington Ultra Magnum". The most widespread of these cartridges are the "SuperMag" family of super-magnum handgun cartridges that were proposed and tested by Elgin Gates in the 1970s.

The following are terms related to firearms and ammunition topics.

<span class="mw-page-title-main">Taurus Judge</span> Revolver

The Taurus Judge is a five shot revolver designed and produced by Taurus International, chambered for .410 bore shot shells and the .45 Colt cartridge. Taurus promotes the Judge as a self-defense tool against carjacking and for home protection.

References

  1. 1 2 3 4 5 6 "FreeDiveList FAQ". Archived from the original on 2007-12-15.
  2. 1 2 3 "Beco Inner Space Products On-Line Catalog".
  3. 1 2 3 "Revenue Ruling 55-569, C.B. 1955-2, 483". Archived from the original on July 19, 2001.
  4. "Alligator Hunting" (PDF). Archived from the original (PDF) on May 24, 2011.
  5. USpatent 4058062,Rhett McNair,"Powerhead cartridge",issued 1977-3-21