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Shotgun Ammunition(組圖)

(2009-12-24 21:43:04) 下一個


Shotgun Ammunition

Note: the material presented on this page cannot be regarded as promotion of ammunition or firearms. The aim of this article is just providing awareness of existing types of shotgun ammunition with their basic characteristics for educational purposes. We warn our readers that shotgun ammunition can cause potential danger to the people and must be kept only in specially equipped storage places admitting no access to unauthorized persons and children. All the actions connected with the purchase/sale and possession of ammunition must be taken only in agreement with current firearms laws or penal legislation. Anyhow, we don’t impel you to own ammunition or guns to avoid possible troubles. If you however decide to purchase ammunition, check your local gun laws before. This site has never been associated with any manufacturer of ammunition or weapons.

Shotgun ammunition - shells (cartridges) with different types of a projectile (birdshot, buckshot or slug) created to be fired from a shotgun. Extremely wide assortment of ammunition makes shotgun a quite versatile weapon used both for small game and large animals hunting, law enforcement, personal defense and even military purposes. Shot and slugs are typically made of lead, but nowadays lead shot is prohibited from use in some areas and replaced with steel one for the ecological reasons. Shotgun ammunition designed for special purposes may be loaded with rubber buckshot or bullets, chemical irritants (tear gas), flares (for signaling), armor-piercing slugs, small dart shaped projectiles. Modern shotgun shell typically consists of a plastic case, with the base covered in a thin brass covering, with primer fixed in a center of a base. Gunpowder, wads and projectile fill the volume of a shotgun shell’s case. The load of a birdshot or buckshot in a cartridge is covered with a shot cup that keeps shell closed, and its rim part is crimped. Wadding plays very important role in obtaining quality shot – it ensures combustion gases sealing and prevents undesirable deformation of projectile.


Construction of slug shotgun cartridge

Construction of shotgun cartridge with a birdshot load

Various shapes of shotgun slugs

Shotgun cartridges are generally classified by gauge, which is a measure related to the diameter of the smooth shotgun bore and the size of the shell designed for that bore. Gauge is the number of equal sized lead spheres that weigh a pound and just fit into the barrel. Thus, the smaller the gauge number, the larger the shotgun bore. For example, one pound of lead divides into 12 equal spheres, 18.5 mm in diameter, and therefore 18.5 mm is the real diameter of 12 gauge shotgun bore. But .410 caliber drops out of this classification – it’s the measurement of the actual bore diameter in a fraction of inch (d=0.410x25.4mm = 10.4 mm). Nowadays 12 gauge is most commonly used in the world; 20 and 28 gauge with .410 calibre are also prevealing. Until mid-20th century 16 gauge was also widespread being very popular among European hunters, but today it’s mostly replaced with 12 gauge. Some exotic shotgun gauges like 10 and 4 are also awailable, but such cannons have limited application.

Shotgun gauges

GaugeBore diameter,
mm
426
1019.7
1218.5
1616.9
2015.7
2814.0
.410 caliber10.4

It is important to use appropriate shotgun cartridges that correspont to the chamber length of your gun. Modern shotguns usually have chamber length 70 mm (2 3/4”) and 76 mm (3”). Larger chamber length allows usage of more powerful ammunition. Thus, 12/76 ammunition is fit to be fired from 12 gauge shotgun with 76 mm (3”) chamber. Never try to use such ammunition with 12 gauge shotgun chambered in 70 mm – most probably it will cause barrel explosion. If the length of shell exceeds the chamber length (when placing 3” shell in 2 3/4” chamber), the shell will not be able to fully open and cause a constriction at the forcing cone. Hence, pressure inside the barrel tremendously increases that leads to damage of the gun and shooter.

Basic ballistic characteristics of slug shotgun ammunition in comparison with some handgun ammo

Gauge/CaliberTypeWeight of bullet,
g
Muzzle velocity,
m/s
Muzzle energy,
J
1212/70 (2 3/4”)324503240
1212/76 (3”)404554140
2020/70 (2 3/4”)254452475
.410 .410/76 (3”)75451040
.41 .41 Remington Magnum13.63961066
9.0 mm9x19 Luger (Parabellum) 7.5345450

12 gauge shotgun ammo

12 Gauge is worldwide-accepted as standard in law enforcement and guarding services due to its high versatility and great firepower. Average slug ammunition 9provides sufficiently high accuracy at medium range (it is possible for ordinary shooter to hit 4” (in radius) circle from 75 m and 2” circle from 50 m). Fired from 20 m distance, 12 gauge slug penetrates steel house door. At this range it also penetrates rear end of non-armored automobile, a back seat, and still retains lethal energy. The most common type of ammunition for police use is a buckshot cartridge. Conventional police shell contains 9 pellets of 8.4 mm buckshot. One shot with this ammo is equivalent to 9 shots from 9 mm pistol. At 15 m distance such load covers 14.5” (in radius) circle target. At short range (15-20 m) this buckshot load penetrates door, rear end and a back seat of standard automobile, retaining lethal energy. The larger buckshot is, the greater its penetration ability.
What sort of ammo to choose for self defense? The use of heavy projectile loads is not reasonable in the case of 12 gauge ammunition, because anyway this ammo provides shooter with excessive firepower that’s more than enough for self protection. Moreover, lite ammo produces less recoil that makes shot more comfortable in comparison with heavy Magnum shells. Thus, recommended projectile weight for self defense 12 gauge ammunition is ~30 g. Since, according to the e xisting statistics, typical distances for self defense spread only up to 10 m, the use of cartridges containing medium or large size birdshot (that are quite efficient at this range) is rational. It is not recommended to apply large buckshot or slug shells for self defense because of their potential for over-penetration and collateral damage. Nevertheless, keep some stock of buckshot and slug ammunition for critical situations. Consider about purchasing non-lethal ammunition (with rubber bullets or buckshot) – such ammo can produce strong knock out effect without causing dangerous injuries to enemies.

20 gauge shotgun ammo

In spite of the fact that 20 gauge is distinctly smaller than 12, it retains great firepower. Due to this circumstance along with the fact that 20 gauge ammo produce considerably less recoil as compared to 12 gauge, this gauge gained wide popularity. In comparison with 12 gauge shotguns, 20 gauge ones are usually lighter and more maneuverable.
20 gauge is very suitable for self defense. The selection of ammunition for this purpose mostly similar to the case of 12 gauge – medium size birdshot loads for close range shooting along with a buckshot and slug ammo for life & death cases.

.410 caliber shotgun ammo

It is prevalent point of view, that .410 caliber shotguns are not effective for self defense due to their insufficient stopping power. This opinion is not correct at all, because at short distances those are typical for self defense shooting, the kinetic energy of .410 caliber slug is comparable with the energy of extremely powerful .41 magnum revolver bullet, which outstanding stopping power is beyond question. According to the firepower level, we can place .410 slug shotgun ammunition in a one line with the most powerful handgun ammo. As we can see from the table displayed above, 12 and 20 gauge shotgun ammunition greatly surpass .410 ammo in energy, but it’s not the reason to regard .410 ammo as something deficient. But the matter of ammo selection for self defense becomes most important in the case of .410 caliber. Birdshot and buckshot shells are not effective enough to ensure considerable stopping effect, so slug .410 ammo is most suitable for self defense. Such cartridges as Winchester Super-X .410/3” contain 1/4 oz slugs and can be regarded as moderately powerful ammo; it’s not recommended to choose slug shells with less projectile weight. Unfortunately, it’s not easy to find heavy .410 slug ammo for defensive purposes, but DIY cartridges might be solution. We recommend to take 11-14 g slugs for making DIY shells and use metal cases.


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