The hinged cover over the opening through which cartridges are inserted into the magazine.
A swing-out arm on a revolver, to which the cylinder is mounted when opened facilitates loading and cleaning.
System of measurement for the internal bore diameter of a smooth-bore firearm based on the diameter of each of that number of spherical lead balls whose total weight equals one pound. The internal diameter of a 12 gauge shotgun barrel is therefore equal to the diameter of a lead ball weighing 1/12 pound, which happens to be .729" (Or in British: Bore.) The Gauge/Bore system is also used, by convention, to describe the internal barrel diameter of large-bore, 19th century, English, single-shot and double-barrel rifles.
A firearm with a coil-spring-actuated firing pin, or with its hammer enclosed inside the action body; i.e.. no externally visible hammer.
The term used for the casing on modern rifle and pistol ammunition. It is usually made out of brass but can also be aluminum or steel. The casing on a shotgun shell is usually refered to as a hull
The unalienable right of all of the people, stated in the Second Article of The Bill of Rights, to possess and use personally owned firearms for sport, recreation, personal protection, and the defense of the nation.
A type of gun barrel rifling where the traditional lands and grooves are replaced by "hills and valleys" in a rounded polygonal pattern, usually a hexagon or octagon. Polygons with a larger number of edges provide a better gas seal in relatively large diameter polygonally rifled bores.
The top of the butt-end of a gun stock.
Slang for Recoil.
The point of the trigger's return at which the gun's internal mechanisms are ready to fire another round.
A metal jacketed bullet design in which the nose of the core of the bullet is exposed to ensure the expansion of the bullet upon impact. Often abbreviated "JSP" or "SP." They tend to expand more slowly than a Hollow Point bullet and are used where deeper penetration and expansion are needed.
An economical method of bringing new life to a damaged pair of barrels, regardless of their original method of jointing. The ribs are removed. The barrels are cut off 3" - 4" from the breech end and discarded. The bores of the remaining breech-end are reamed out oversize. New tubes are fitted down into the original breech section and filed down to fit flush. The original ribs are then replaced. Sleeving is considerably less expensive than building a completely new set of barrels. Much of the time required to build a set of barrels is concentrated in the fitting of the breech end to the receiver; this work is salvaged through sleeving. Sleeving can be recognized by a pair of circumferential lines around the barrels a few inches from the breech; the more invisible, the finer the job. A sleeved gun should always be identified as such amongst the proof marks, and if done in England must be properly reproofed. Photo Sleeving is not the same thing as Monoblocking.
Abbreviation for Course of Fire.
The portion of the receiver which is threaded so the barrel can be attached to it.
The degree to which the barrel(s) of a break-open gun drop down; the size of the opening space, which should be sufficient to allow for ease of loading, unloading and properly-functioning ejection. A good gape is easier to achieve on a side-by-side than an over & under where the bottom barrel is well-enclosed by the action body.
A condition on a shooting range that is completely safe. Any firearms at the range are on the benches, unloaded with open actions and all people have stepped away from the firing line.
Generally refers to the stock and fore-end of a rifle. Can sometimes also be applied to any detachable accessories like a flashlight.
A shooting position in which one or both knees are touching the ground, but the shooter is otherwise erect.
The rear sight is placed at the end of the barrel nearest the shooter. It may be in the shape of a square notch, a U, a V, a ring, or simply two dots designed to be visually placed on either side of the front sight while shooting.
The practice of modifying military-type firearms either to make them suitable for civilian sporting use. Common sporterizing includes changing the stock or sights.