A shotgun is a long-barreled firearm designed to shoot a straight-walled cartridge known as a shotshell, which usually discharges numerous small pellet-like spherical sub-projectiles called shot, or sometimes a single solid projectile called a slug. Shotguns are most commonly smoothbore firearms, meaning that their gun barrels have no rifling on the inner wall, but rifled barrels for shooting slugs are also available.
A cartridge or 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 the practical purpose of convenient transportation and handling during shooting. Although in popular usage the term "bullet" is often informally used to refer to a complete cartridge, it is correctly used only to refer to the projectile.
In guns, particularly firearms, caliber is the specified nominal internal diameter of the gun barrel bore - regardless of how or where the bore is measured and whether the finished bore matches that specification. It is measured in inches or in millimeters. In the United States it is expressed in hundredths of an inch; in the United Kingdom in thousandths; in Europe and elsewhere in millimeters. For example, a "45 caliber" firearm has a barrel diameter of roughly 0.45 inches (11 mm). Barrel diameters can also be expressed using metric dimensions. For example, a "9 mm pistol" has a barrel diameter of about 9 millimeters. Due to the fact that metric and US customary units do not convert evenly at this scale, metric conversions of caliber measured in decimal inches are typically approximations of the precise specifications in non-metric units, and vice versa.
Terminal ballistics is a sub-field of ballistics concerned with the behavior and effects of a projectile when it hits and transfers its energy to a target.
International Rifle events that occur in three positions are conducted with an equal number of shots fired from the Prone, the Standing and the Kneeling positions, always in that order. Each of the three positions shot during the match has a fixed time limit that the shooter is able to shoot unlimited numbers of sighting shots and 10 or 20 shots for record.
A wadcutter is a special-purpose flat-fronted bullet specifically designed for shooting paper targets, usually at close range and at subsonic velocities typically under approximately 900 ft/s (274 m/s). Wadcutters have also found favor for use in self-defense guns, such as .38 caliber snubnosed revolvers, where, due to short barrel lengths, maximum bullet velocities are usually low, typically under 900 ft/s (274 m/s), and improved lethality is desired. Wadcutters are often used in handgun and airgun competitions.
Iron sights are a system of physical alignment markers used as a sighting device to assist the accurate aiming of ranged weapons, or less commonly as a primitive finder sight for optical telescopes. The earliest sighting device, it relies completely on the viewer's naked eye, and is distinctly different to optical sights such as telescopic sights, reflector (reflex) sights, holographic sights and laser sights, which make use of optical manipulation and/or active illumination, as well as the newer optoelectronics, which use digital imaging and even incorporate augmented reality.
A bore gauge is a collective term for the tools that are unique to the process of accurately measuring holes.
The gauge of a firearm is a unit of measurement used to express the inner diameter of the barrel.
Benchrest shooting is a shooting sport discipline in which high-precision rifles are rested on a table or bench — rather than being carried in the shooter's hands — while shooting at paper or steel targets, hence the name "benchrest". Both the forearm and buttstock of such a rifle are usually fully supported by bean bags, a bipod/monopod (front/rear) combination, and/or a specially designed fixture device called shooting rest, so that the gun can remain stably pointing at the target without needing to be held by someone. When shooting, the shooter simply sits/stands comfortably behind the table/bench, operates the action and pulls the trigger, without needing to worry about carrying any weight of the gun. This is in contrast to other shooting disciplines, where the shooter has to bear at least part of the gun's weight while holding it steady to aim, even when using support devices such as bipods, tripods or shooting sticks.
The Civilian Marksmanship Program (CMP) is a U.S. government-chartered program intended to promote firearm safety training and rifle practice for all qualified U.S. citizens with a specific emphasis on youth. Any U.S. citizen not otherwise legally prohibited from owning a firearm may purchase a military surplus rifle from the CMP, provided they are a member of a CMP affiliated club. The CMP operates through a network of affiliated private organizations, shooting clubs, and state associations across every state in the U.S which variously offer firearms safety training and marksmanship courses as well as continued practice and competition events.
NRA Precision Pistol, formerly known as NRA Conventional Pistol, is a national bullseye shooting discipline organized in the United States by NRA. Emphasis is on accuracy and precision, and participants shoot handguns at paper targets at fixed distances and time limits. Other organizations in the United States and Canada have established rules and keep records of similar disciplines, including the Civilian Marksmanship Program (CMP) in the United States,.
10 meter air rifle is an International Shooting Sports Federation (ISSF) shooting event, shot at a bullseye target over a distance of 10 meters using a 4.5 mm (0.177 in) calibre air rifle with a maximum weight of 5.5 kg (12.13 lb). It is one of the ISSF-governed shooting sports included in the Summer Olympics since the 1984 Los Angeles Games.
The .45-70 rifle cartridge, also known as .45-70 Government, was developed at the U.S. Army's Springfield Armory for use in the Springfield Model 1873, which is known to collectors as the "Trapdoor Springfield." The new cartridge was a replacement for the stop-gap .50-70 Government cartridge, which had been adopted in 1866, one year after the end of the American Civil War.
A heeled bullet is a specific design of bullet where the internal diameter of the barrel is often, but not always, the same diameter as the cartridge case, and the bullet has a step at the rear to allow it to fit inside the case. Heeled bullets mostly disappeared with the advent of smokeless powder cartridges, though older rimfire designs, such as the .22 caliber rimfire cartridges, still use heeled bullets, and many cartridges that date back to the black powder era still reflect their heeled bullet origins in their caliber designations.
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. Alternative names sometimes imply the type of dimensional difference. A chamber insert may be used for a shorter cartridge of similar base diameter. A supplemental chamber or cartridge adapter is typically used for a shorter cartridge of reduced diameter. A cartridge conversion sleeve may include a short barrel of reduced bore diameter. Shotgun conversion sleeves may be called subgauge inserts, subgauge tubes, or gauge reducers. Sleeves intended for rifle or handgun cartridges may have rifled barrels. Additional variations may allow centerfire weapons to fire rimfire ammunition and/or retain autoloading function with the smaller cartridge.
The following are terms related to firearms and ammunition topics.
Power Factor (PF) in practical shooting competitions refers to a ranking system used to reward cartridges with more recoil. Power factor is a measure of the momentum of the bullet, which to some degree reflect the recoil impulse from the firearm onto the shooter.
High Power Rifle, also called XTC from "Across the Course", is a shooting sport using fullbore target rifles which is arranged in the United States by the National Rifle Association of America. The sport is divided into classes by equipment, and popular types of matches include Service Rifle, Open, Axis and Allies and metallic silhouette. The term High Power Rifle sometimes also includes the international shooting disciplines of Palma and F-Class by the International Confederation of Fullbore Rifle Associations (ICFRA) which are represented by the NRA in the United States.
Steel targets are shooting targets made out of hardened (martensitic) steel, and are used in firearm and airgun sports such as silhouette shooting, cowboy action shooting, practical/dynamic shooting, long range shooting and field target, as well as recreational plinking. They are popular in both training and competitions because the shooter gets instant acoustic feedback on a successful impact, and can often also visually confirm hits by seeing the bullet getting pulverized, leaving a mark on the surface paint, or moving/knocking down the target. Hanging steel plates or self-resetting steel targets also have the advantage that the shooter does not need to go forward downrange to tape the targets, making it a good option for shooting ranges that otherwise have electronic targets. Steel targets also are weatherproof, contrary to paper targets, which do not hold up in rain and wind gusts.
