The Definition of Gauge
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.
19 Other Firearms Definitions You Need To Know
A metal surface which contains a pattern of ridges or beads.
Two firearms that are manufactured identical in every way and are sequentially serial numbered and are sold as a set.
The most common type of matched pair guns are cowboy style revolvers for a couple of reasons, both guns will feel exactly the same in the hands and they make the set more collectable.
The mechanism of some firearms that holds the cartridge in place during the firing process.
It must be moved out of the way to load and unload the gun; this action may be manually performed
by the shooter pulling back on an exterior knob called the bolt handle and then sending it forward again, or the action may be performed
by other moving parts within the firearm. When the user must move the bolt manually, the firearm is called a bolt-action firearm.
Slang word abreviation for Ammunition.
Two shots fired very quickly with the use of the sights.
Crude adjustments made to an optical firearm sight, or iron sights, to align the firearm barrel and sights.
This method is usually used to pre-align the sights, which makes zeroing (zero drop at XX distance) much faster.
The portion of the stock (on a rifle) or frame (on a pistol) gripped by the trigger hand.
Anything that will safely stop a bullet and prevent it from hitting anything else after the target is struck.
For self-defensive shooters, Center Of Mass (COM) represents the area of an attackers torso within which the most vital organs are likely to be disrupted by a gunshot.
Shooting to COM is considered the most expedient way to stop an assailant from continuing threatening behavior.
Simple clips made of metal or sometimes plastic that hold several rounds of ammunition in a row and is used to quickly fill a magazine.
Sloppy movement (slack) of a trigger before the actual point of let-off.
The NRA teaches the Three Basic Rules of Safe Gun Handling.
There are additional rules, but these are the three that if any two are followed, nobody will be hurt. However, obviously, all three should
always be followed.
Rule One: ALWAYS keep the gun pointed in a safe direction.
The NRA established these three rules in 1871. They were created to be easy to understand and remember,
ensuring the highest possible level of firearm safety.
Rule Two: ALWAYS keep your finger off the trigger until ready to shoot.
Rule Three: ALWAYS keep the gun unloaded until ready to use.
See also The Four Rules
A sidelock action where the mainspring is mounted rearward towards the butt.
The back action is often used in double rifles where the need for strength requires as
little steel as possible be removed from the bar of the action.
The face of the action of a break-open firearm which houses the firing pins and receives the direct recoil of the fired round.
Rifling that is formed by pulling a die made with reverse image of the rifling (the 'button') down the pre-drilled bore of a firearm barrel.
Abbreviation for Concealed Firearms Permit.
Abbreviation for 'Bad Guy'
A catch built into the receiver of a break-open gun to keep the toplever in its extreme right position when the barrels are removed.
This device makes it slightly easier to remount the barrels. As the barrels are mounted and the breech closed,
the barrels contact some kind of release pin (marked with the arrow) and the toplever automatically returns
to the center locked position. Because, however, it requires a separate act to find and to depress this tiny
tab to re-center the toplever on a broken-down gun, this feature may be irritating when trying to put a gun away in its case.