Because of all this, they are extremely lethal, even at range, and as such, they are mainly used by hunters who need the power at distance. It compares the ballistics trajectory of the 1oz slug from a 12 gauge to q 9mm round. What it shows is that the 12 gauge slug will travel pretty flat for up to yards with perhaps 10 to 12 inches of drop at yards.
At yards the chart shows a drop of about 4 feet. This was from a firearms study and suggests the absolute maximum a slug can travel is around feet yards. So at yards, a 12 gauge slug is traveling 5 times the speed needed to break a bone.
As the above ballistics prove, a 12 gauge slug has a flat trajectory out to about yards, so if you are a good shot with an iron sight, then you should be good to go.
So the actual answer is zero. The team tries slugs at yards, yards, yards, and yards to determine their range and lethality. The slugs used are 1oz slugs from Federal, birdshot, and 27 pellet buckshot. The round will travel and is still lethal at over yards though. After that, it becomes a little prone to wind and other aerodynamics.
If you are shooting at yards or so, you have nothing to worry about as it has a lovely flat trajectory. Good stuff! The actual purpose of the fins is to allow the slug to be safely swaged down when fired through a choked shotgun barrel, although accuracy will suffer when such a slug is fired through chokes tighter than improved cylinder.
Cylinder choke is the one recommended for best use. As with all shotgun slugs, it is possible to fire Foster slugs through a Shotgun Slug,1 that is rifled, Barrel. It should be noted, however, that as the slug is not lubricated, leading of the rifled portion of the barrel becomes a great problem necessitating regular cleaning to maintain any degree of accuracy. The main characteristic of a sabot slug is the plastic carrier or sabot, which is of bore size or sometimes a little larger to enable the sabot to engage the rifling found in modern slug barrels.
The slugs contained in sabots can be anything up to 0. Those for police use are usually of a solid hard metal alloy material for barricade penetration or door lock and hinge removal. Although the sabot slug is used primarily in rifled barrels , some designs of sabot slugs can be fired in smooth-bore shotguns most notably the Brenneke Rubin Sabot , a sub-calibre slug utilizing the familiar Brenneke attached wad system.
The smaller projectile held within sabots will have a much flatter trajectory, and will travel at much higher velocities than the more traditional foster or rifled slug. Saboted slugs will, when fired from a rifled barrel, produce near rifle-type accuracy. Another advantage of the sabot type of shotgun slug is that no lead comes into contact with the barrel, thus preventing lead fouling. Penetration of foster and sabot slugs.
The following table gives an indication of the penetration potential of shotgun slugs. Penetration figures for normal shot are for comparison purposes. It is generally accepted by those involved in the wound ballistics field that a minimum penetration of 12 in. To illustrate the penetration potential of shotgun slugs, the test was carried out using standard NATO 0.
Buckshot loads are shown for comparison purposes. The common misconception is that the shotgun slug has an extremely short range as well as a very poor trajectory. This is not quite true, although past yd, the velocity and hence kinetic energy does drop off quite considerably.
Other types of specialized, single missile, shotgun ammunition include the breaching or Hatton cartridge and tear-gas rounds. The Hatton round is made specifically for police or military use and is designed for the breaching of doorways. It is typically fired at a range of in. It can also be used to remove the hinges in a similar way. The missile is a single bore, frangible slug weighing gr 1. The round is made of compressed zinc or lead powder bonded with hard wax.
When fired, the full force of the round is delivered to the target, minimizing the risk. Ultimate Firearms Training Guide. Combat Fighter System. The flight path of a bullet includes: travel down the barrel, path through the air, and path through a target.
The wounding potential of projectiles is a complex matter. Fackler, Bullets fired from a rifle will have more energy than similar bullets fired from a handgun. More powder can also be used in rifle cartridges because the bullet chambers can be designed to withstand greater pressures 50, to 70, for rifles psi vs. Higher pressures require a bigger gun with more recoil that is slower to load and generates more heat that produces more wear on the metal.
It is difficult in practice to measure the forces within a gun barrel, but the one easily measured parameter is the velocity with which the bullet exits the barrel muzzle velocity and this measurement will be used in examples below. Bruner et al, The area here is the base of the bullet equivalent to diameter of barrel and is a constant.
Therefore, the energy transmitted to the bullet with a given mass will depend upon mass times force times the time interval over which the force is applied.
The last of these factors is a function of barrel length. Bullet travel through a gun barrel is characterized by increasing acceleration as the expanding gases push on it, but decreasing pressure in the barrel as the gas expands. Up to a point of diminishing pressure, the longer the barrel, the greater the acceleration of the bullet.
Volgas, Stannard and Alonso, As the bullet traverses the barrel of the gun, some minor deformation occurs, called setback deformation. This results from minor rarely major imperfections or variations in rifling or tool marks within the barrel. The effect upon the subsequent flight path of the bullet is usually insignificant.
Jandial et al, The external ballistics of a bullet's path can be determined by several formulae, the simplest of which is:. This is the bullet's energy as it leaves the muzzle, but the ballistic coefficient BC will determine the amount of KE delivered to the target as air resistance is encountered. Thus, greater velocity, greater caliber, or denser tissue gives more drag. The degree to which a bullet is slowed by drag is called retardation r given by the formula:. SD is the sectional density of the bullet, and I is a form factor for the bullet shape.
Sectional density is calculated from the bullet mass M divided by the square of its diameter. The form factor value I decreases with increasing pointedness of the bullet a sphere would have the highest I value. Since drag D is a function of velocity, it can be seen that for a bullet of a given mass M , the greater the velocity, the greater the retardation.
Drag is also influenced by bullet spin. The faster the spin, the less likely a bullet will "yaw" or turn sideways and tumble in its flight path through the air. Thus, increasing the twist of the rifling from 1 in 7 will impart greater spin than the typical 1 in 12 spiral one turn in 12 inches of barrel. Bullets do not typically follow a straight line to the target. Rotational forces are in effect that keep the bullet off a straight axis of flight.
These rotational effects are diagrammed below:. Yaw refers to the rotation of the nose of the bullet away from the line of flight. Precession refers to rotation of the bullet around the center of mass. Nutation refers to small circular movement at the bullet tip. Yaw and precession decrease as the distance of the bullet from the barrel increases.
What do all these formulae mean in terms of designing cartridges and bullets? Well, given that a cartridge can be only so large to fit in a chamber, and given that the steel of the chamber can handle only so much pressure from increasing the amount of gunpowder, the kinetic energy for any given weapon is increased more easily by increasing bullet mass.
Though the square of the velocity would increase KE much more, it is practically very difficult to increase velocity, which is dependent upon the amount of gunpowder burned.
There is only so much gunpowder that can burned efficiently in a cartridge. Thus, cartridges designed for hunting big game animals use very large bullets.
To reduce air resistance, the ideal bullet would be a long, heavy needle, but such a projectile would go right through the target without dispersing much of its energy.
Light spheres would be retarded the greatest within tissues and release more energy, but might not even get to the target. A good aerodynamic compromise bullet shape is a parbolic curve with low frontal area and wind-splitting shape. The best bullet composition is lead Pb which is of high density and is cheap to obtain.
Alloying the lead Pb with a small amount of antimony Sb helps, but the real answer is to interface the lead bullet with the hard steel barrel through another metal soft enough to seal the bullet in the barrel but of high melting point.
Copper Cu works best as this "jacket" material for lead. Yaw has a lot to do with the injury pattern of a bullet on the target, termed "terminal ballistics. This causes more tissue to be displaced, increases drag, and imparts more of the KE to the target. A longer, heavier bullet might have more KE at a longer range when it hits the target, but it may penetrate so well that it exits the target with much of its KE remaining.
Even a bullet with a low KE can impart significant tissue damage if it can be designed to give up all of the KE into the target, and the target is at short range as with handguns. Despite yaw, an intact bullet that comes to rest in tissue generally has its long axis aligned along the path of the bullet track, though its final position may be either nose forward or base forward. Laceration and crushing - Tissue damage through laceration and crushing occurs along the path or "track" through the body that a projectile, or its fragments, may produce.
The diameter of the crush injury in tissue is the diameter of the bullet or fragment, up to the long axis. Cavitation - A "permanent" cavity is caused by the path track of the bullet itself with crushing of tissue, whereas a "temporary" cavity is formed by radial stretching around the bullet track from continued acceleration of the medium air or tissue in the wake of the bullet, causing the wound cavity to be stretched outward.
For projectiles traveling at low velocity the permanent and temporary cavities are nearly the same, but at high velocity and with bullet yaw the temporary cavity becomes larger Maiden, Shock waves - Shock waves compress the medium and travel ahead of the bullet, as well as to the sides, but these waves last only a few microseconds and do not cause profound destruction at low velocity.
At high velocity, generated shock waves can reach up to atmospheres of pressure. DiMaio and Zumwalt, However, bone fracture from cavitation is an extremely rare event. Fackler, The ballistic pressure wave from distant bullet impact can induce a concussive-like effect in humans, causing acute neurological symptoms. Courtney and Courtney, The mathematics of wound ballistics, in reference to yaw of unstable projectiles, has been described.
The model works well for non-deformable bullets. Peters et al, Peters and Sebourn, Experimental methods to demonstrate tissue damage have utilized materials with characteristics similar to human soft tissues and skin.
Pigskin has been employed to provide an external layer to blocks of compounds such as ordnance gelatin or ballistic soap. Firing of bullets into these materials at various ranges is followed by direct visual inspection cutting the block or radiographic analysis CT imaging to determine the sizes and appearances of the cavity produced Rutty, et al, The following images illustrate bullet deformation and damage:.
Bullet velocity and mass will affect the nature of wounding. Wilson, An M rifle. A hunting rifle. Bullet design is important in wounding potential.
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