- Captive bolt pistol
A captive bolt pistol (also variously known as a cattle gun, stunbolt gun, bolt gun, or stunner) is a device used for
stunning animals prior to slaughter. Proper stunning is essential to prevent the pain and suffering of the animal during thebleeding (exsanguination ) process (which is itself necessary to preventmeat spoilage ) duringbutcher ing.The principle behindcaptive bolt stunning is a forceful strike on theforehead using a bolt to induceunconsciousness . The bolt may or may not destroy part of thebrain .The bolt is a heavy rod made of non-rusting alloys, such as
stainless steel . It is held in position inside the barrel of the stunner by means of rubber washers. The bolt is usually not visible in a stunner in good condition. The bolt is actuated by atrigger pull and is propelled forward by compressed air or by the discharge of a blank round ignited by a firing pin. After striking a shallow but forceful blow on (or through) the forehead of the animal, spring tension causes the bolt to recoil back into the barrel.Variations
The captive bolt pistols are of three types: penetrating, non-penetrating, and free bolt.
In the penetrating type, the stunner uses a pointed
bolt which is propelled by pressurized air or ablank cartridge . The bolt penetrates theskull of the animal, enters the cranium, and catastrophically damages the cerebrum and part of thecerebellum . Due toconcussion , destruction of vital centres ofbrain and an increase inintracranial pressure , the animal loses consciousness. This method is currently the most effective and widely used type of stunning, since it physically destroys brain matter (increasing the probability of a successful stun), while also leaving thebrain stem intact (thus ensuring the heart continues to beat, facilitating a successful bleed). One disadvantage of this method is that brain matter is allowed into theblood stream , possibly contaminating other tissue withbovine spongiform encephalopathy (B.S.E., commonly known as Mad Cow Disease) . The action of a non-penetrating stunner is similar, but the bolt is blunt with amushroom -shaped tip. The bolt strikes the forehead with great force and immediately retracts. This concussion is responsible for the unconsciousness of the animal. This type of stunner is less reliable at causing immediate and permanent unconsciousness than penetrating types; however, it has undergone a resurgence of popularity due to concerns about mad cow disease. In theEuropean Union , this captive bolt design is required for slaughter of animals that will be used forpharmaceutical manufacture. [ [http://www.emea.europa.eu/pdfs/human/bwp/TSE%20NFG%20410-rev2.pdf Note for guidance on minimising the risk of transmitting animal spongiform encephalophathy agents.] ]The free bolt stunner is used for the emergency in-the-field euthanasia of large farm-animals who cannot be restrained. It differs from a true captive bolt gun in that the projectile is not retractable; it is similar in operation to a powder-actuated
nail gun or conventional firearm. Capable of firing only when pressed firmly against a surface (typically the animal's forehead), the device fires a small projectile through the animal's skull. Theveterinarian can then either leave the animal to expire from the projectile wound, or administerlethal drugs .Use
With
cattle ,goats , andsheep , a penetrating stunner is typically used since it destroys thecerebrum while leaving thebrain stem intact; this results in a more consistently reliable stun, and ensures the animal's heart continues to beat during thebleeding process. In someveal operations, a non-penetrating concussive stunner is used in order to preserve the brains for further processing.Captive bolt stunners are safer to use in most red meat slaughter situations. There is no danger of
ricochet or over-penetration as there is with regular firearms.Captive bolts allow for meat trimming from the head to be salvaged.
Most animals are stunned at a place on the forehead or pate above the eyes. Some animals, such as old Hereford cattle, which have too much hair on the forehead or pate, and bulls, which have too thick a skull, are stunned at the back of the poll. This is known as poll knocking. It can render livestock unconscious, but may require more attempts since the placement of the bolt is more difficult (place the bolt in the space where the skull meets the head in the depression that it makes).
The cartridges typically use two to three grains (130 to 190 M.G.) of
gunpowder , but can use up to seven grains (450 M.G.) in the case of large animals such as bulls. The velocity of the bolt is usually 55 m/s in the case of small animals and 75 m/s in the case of large animals.There are certain specific stunning sites for various animals:
*Bull andcow : The stunning site is at or below the point of intersection of two imaginary lines drawn from the base of each horn to the inner canthus of the opposite eye.
*Pig : The stunning site is on the forehead at a point 25 M.M. above the eyes. The stunner should be directed towards thegullet .
*Sheep andgoat : The stunning site is below the ridge which runs under the base of the horn. The direction of shot is towards the gullet.For all polled animals, the site is at the center of forehead, the shot being directed towards thegullet .In popular culture
In the novel "
No Country For Old Men " and its Oscar-winning 2007 film adaptation, the killer Anton Chigurh uses a captive bolt pistol to kill several people and to punch outcylinder lock s on doors.In
Dick Francis 's novel "Bolt", the villain terrorizes characters by killing their horses with a captive bolt pistol.The captive bolt stunner is described in Eric Schlosser's 2001
book "Fast Food Nation ", and footage showing its use in aslaughterhouse appears in the film adaptation.In the 1983 novel "Cal", an I.R.A. member Crilly uses a captive bolt pistol to kneecap fellow paramilitaries. The victims subsequently develop a limp, pointing them out as
traitor s to others. In the novel, the man uses a captive bolt pistol because he believes "it doesn't leave a trace". Ironically this is what leads investigators to him and hisparamilitary unit.A captive bolt pistol is used to commit
murder in the book andfilm adaptation of "The Butcher Boy ".The 1992 German film "
Benny's Video " features a captive bolt pistol in the killing of apig for slaughter and also in the commission of a murder by the title character.In
Neil Gaiman 's novel "American Gods ", Czernobog discusses the use of the captive bolt pistol in a slaughterhouse as part of a history of his work in themeatpacking industry .In the
video game ""Agent 47 can use a bolt pistol to eliminate his targets in the level 'The Meat King's Party'.The
comic book "" features an unnamed villain who uses a captive bolt pistol (referred to as a "bolt stunner") to murder one teenager and knock another unconscious.The
Deli Creeps song "Boom Ch Ka," a song written aboutMcDonald's and the slaughter of cattle used in theirburger s, is named after the sound created when the bolt is fired.The television show Bones referenced a bolt pistol as the weapon of choice for a hitman tied to Dr. Temperance Brennan's
fugitive parents. The use of the bolt pistol was the unique signature that led to additional charges for thishitman .One of the first occurrences of the captive bolt pistol in a detective story can be found in the 1935
novel "The Unicorn Murders " by Carter Dickson (one of the pen names ofJohn Dickson Carr ).References
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