Hollow point bullet
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A hollow point bullet is a bullet that has a pit, or hollowed out shape, in its tip, generally intended to cause the bullet to expand upon entering a soft target in order to increase it's lethal effects. Jacketed hollow points or plated hollow points are covered in a coating of harder metal to increase bullet strength. A hollow-cavity bullet is an extreme variant of a hollow point where the hollow dominates the volume of the bullet and causes extreme expansion or disintegration on impact.
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[edit] How it works
When the bullet strikes a soft target the pressure created in the pit forces the material (usually lead) around the inside edge to expand outward. This change in shape increases the axial diameter of the projectile as it passes through. The greater surface area limits penetration into the target, and causes more tissue damage along the wound path. Many hollow point bullets, especially those intended for use at high velocity, are partially jacketed, that is, a portion of the lead bullet wrapped in a copper casing. This jacket provides additional strength to the bullet, and can help prevent the bullet from leaving deposits of metal inside the bore. In controlled expansion bullets, the jacket helps to prevent the bullet from breaking apart. A fragmented bullet will generally not penetrate to the desired depth.
[edit] History
Solid lead bullets, when cast from a soft alloy, will often deform and provide some expansion if they hit the target at a high velocity. This, combined with the limited velocity and penetration attainable with muzzleloading firearms, meant there was little need for extra expansion.
The first hollow point bullets were marketed in the late 1800s as Express bullets, and were hollowed out to reduce the bullet's mass and provide higher velocities. In addition to providing increased velocities, the hollow also turned out to provide significant expansion, especially when the bullets were cast in a soft lead alloy. Originally intended for rifles, the popular .32-20, .38-40 and .44-40 calibers could also be fired in revolvers.
With the advent of smokeless powder, velocities increased, and bullets got smaller, faster, and lighter. These new bullets (especially in rifles) needed to be jacketed to handle the conditions of firing. The new full metal jacket bullets tended to penetrate straight through a target and produce little damage. This led to the development of the soft point bullet and later jacketed hollow point bullets at the British arsenal in Dum-dum, near Calcutta around 1890. While these were quickly outlawed for use in warfare, they steadily gained ground among hunters due to the ability to control the expansion of the new high velocity cartridges.
Modern hollow point bullet designs use many different methods to provide controlled expansion, including:
- Jackets that are thinner near the front than the rear to allow easy expansion at the beginning, then a reduced expansion rate
- Partitions in the middle of the bullet core to stop expansion at a given point
- Bonding the lead core to the copper jacket to prevent separation
- Fluted or otherwise weakened jackets to encourage expansion or fragmentation
- Posts in the hollow, to prevent clogging of the cavity with materials that may prevent expansion, such as hair and cloth
- Solid copper hollow points, which are far stronger than jacketed lead, and provide very limited expansion even at high velocities
- Plastic inserts in the hollow, which provide the same profile as a full metal jacketed round, but crush on impact to expose the hollows
[edit] Legality
The Hague Convention of 1899, Declaration III, prohibits the use in warfare of bullets which easily expand or flatten in the body. This is often incorrectly believed to be prohibited in the Geneva Conventions, but it significantly predates those conventions, and is in fact a continuance of The Declaration of St Petersburg in 1868, which banned exploding projectiles of less than 400 grams, and weapons designed to aggravate injured soldiers or make their death inevitable. Despite the ban on military use, hollow point bullets are one of the most common types of civilian and police ammunition, due largely to the reduced risk of bystanders being hit by over-penetrating or ricocheted bullets, and the increased speed of incapacitation. In many jurisdictions, it is illegal to hunt game with ammunition that does not expand, and some target ranges also forbid full metal jacket ammunition.
[edit] Winchester Black Talon controversy
In the early 1992 Winchester introduced a newly designed hollow point handgun bullet which used a specially designed, reverse tapered jacket. The jacket was cut at the hollow to intentionally weaken it, and these cuts allowed the jacket to open into six petals upon impact. The thick jacket material kept the tips of the jacket from bending as easily as a normal thickness jacket. The slits that weakened the jacket left triangular shapes in the tip of the jacket, and these triangular sections of jacket would end up pointing out after expanson, leading to the "Talon" name. The bullets were coated with a black colored, paint-like lubricant called "Lubalox," and loaded into nickel-plated brass cases, which made them visually stand out from other defensive ammunition. While actual performance of the Black Talon rounds was not significantly better than any other comparable high performance hollow point ammunition, the reverse taper jacket did provide reliable expansion under a wide range of conditions, and many police departments adopted the round.
Winchester's "Black Talon" product name was eventually used against them. After a high profile shooting at 101 California Street in 1993, media response against Winchester was brutal. "This bullet kills you better", says one report; "its six razorlike claws unfold on impact, expanding to nearly three times the bullet's diameter, "[1] a gross exaggeration of the actual performance[2]. A legitimate concern was raised by the American College of Emergency Physicians, that the sharp edges of the jacket could penetrate surgical gloves, and increase the risk of blood borne infections being transmitted to medical personnel treating the gunshot wound. While possible, there are no recorded cases of such an infection occurring in relation to the Black Talon bullets[3].
Winchester responded to the media attacks on the Black Talon line by pulling it from their civilian marketing channels, and selling it only through Winchester law enforcement distributors. They also discontinued applying the black Lubalox coating and renamed the line "Ranger SXT." The rounded edges had no function effect on the terminal performance, but addressed the ACEP's concerns about possible dangers to medical personnel.
Even though Winchester voluntarily pulled Black Talon from the civilian market, they were subsequently sued for another 1993 shooting, this one in New York, involving Black Talon ammunition. The suit claimed "negligent manufacture, advertising and marketing of a product that was unreasonably designed and ultrahazardous." However, the court found that "The very purpose of the Black Talon bullet is to kill or cause severe wounding. Here, plaintiffs concede that the Black Talons performed precisely as intended by the manufacturer".[4] Since the bullet was designed to cause rapid incapacitation, and since it performed as expected, the lawsuit was dismissed.
[edit] Terminology
The hollow point bullet is sometimes also referred to as the dum-dum, after the arsenal where jacketed, expanding bullets were first developed. This usage is rare among shooters, but can still be found in use. Recreational shooters often refer to hollow points as "JHPs", from the common manufacturer's abbreviation for "Jacketed Hollow Point".
[edit] External links
- A history of commercial hollow point bullet molds, going back to the 1890s.
- Declaration of St. Petersburg, 1868
- Declaration III, Hague Convention of 1899
