Facile Princeps
  • "Easily the Best". A proprietary boxlock action design by W W Greener, similar to the Anson & Deeley, but more easily cocked with the fall of the barrels; the forend iron pressing on a rod passing through the front barrel lump and acting upon cocking bars just below and behind the front Purdey underbolt.
Failure To Extract
  • A semi-automatic firearm malfunction in which the extractor fails to move the empty case out of the way as the slide travels back. A failure to extract often causes double-feed malfunction.
Failure To Feed
  • A semi-automatic firearm malfunction in which the slide passes entirely over the fresh round, failing to pick it up to insert into the chamber as the slide returns to battery.
Failure To Fire
  • Any malfunction that results in no shot fired when the trigger is pulled. Commonly caused by a failure to feed, bad ammunition or a broken firing pin.
Falling Block
  • A type of action used primarily for single shot rifles whereby some kind of lever actuates a breechblock, moving it downwards in a vertical recess to expose the chamber. May have visible or enclosed hammer. For any given barrel length, it allows a shorter overall rifle length compared to a bolt action because no space is taken up by the forward-and-back cycling of the bolt. Most of the better British makers produced them in limited numbers around the turn of the last century, the Farquharson being the most iconic. Perhaps the best-known falling block action today is the Ruger No.1.
False Muzzle
  • An attachment made for the muzzle of an individual rifle barrel in the interest of extreme accuracy. The bullet is loaded through the false muzzle, which begins to swage grooves into the projectile exactly in line with the rifle's bore, and is then ramrodded fully to the breech. Then, the rifle (which can be either breech or muzzle loading) is set up to fire a mechanical bullet, precisely pre-rifled to fit that particular bore. Often used in conjunction with a bullet starter.
Fancy Back
  • Any of a number of different contour variations to the rear of a boxlock action abutting the head of the stock to improve the look and justify a higher price than for a plain gun. Also: Scalloped Receiver.
Farquharson Action
  • One of the classic British falling block single shot rifle actions, patented by John Farquharson in 1872, adopted by George Gibbs and others.


  • Westley Richard's trademark name for a Paradox-rifled-barreled gun, in 20 and 28-bor
Feed Ramp

  • An inclined, polished area on a repeating firearm, just behind the chamber, that helps guide a cartridge into the chamber when pushed forward by the closing bolt.

  • Hemispherical outgrowths of the receiver of a double gun that mate with the breech ends of the barrels. The term derives from the flanges (or fences) in this position on a muzzle loading gun that were designed to protect the eyes of the shooter from sparks and escaping gasses.
FFL Federal Firearms License


  • Federal Firearms [Dealer's] License. Under federal law, to ship a firearm, a selling dealer must have in his possession a copy of the receiving dealer's license.
  • A Federal Firearms License (FFL) is a license in the United States that enables an individual or a company to engage in a business pertaining to the manufacture or importation of firearms and ammunition, or the interstate and intrastate sale of firearms.
Field Forend


  • A relatively slender forend on an over & under gun (as opposed to a beavertail forend). Over & Under counterpart of a Splinter Forend
Field Grade


  • A generic term for a plain, functional, unembellished firearm used to hunt in rough terrain where one might prefer not to put a more expensive, deluxe grade gun at risk of damage.
Field Gun


  • A shotgun, generally stocked to shoot where it is pointed and of relatively light weight because one often carries it a great distance for upland birds---the consequent recoil not being an important factor because one actually shoots it very little.


  • The forward-most part of a sidelock gun's stock; the slender flutes of wood extending along the lockplates, heading up to the receiver body. Also: Horns
Fire Blue


  • A Brilliant, slightly iridescent, and perishable blue finish on highly-polished steel achieved by heating to a temperature of about 500°F. Often seen as small-part details on pre-World War I Colts and the best contemporary American custom rifles.
Fire Form

  • The act of firing a relatively smaller cartridge in a rifle with a relatively somewhat larger chamber in order to expand the cartridge case to the larger size. This action should not be undertaken except in very particular instances or catastrophic damage may occur. It should only be done when the larger chamber is of a closely related design to that of the smaller cartridge case---such as firing a .375 H&H Magnum cartridge in a .375 Weatherby chamber, or firing a .22 Hornet cartridge in a .22  K-Hornet chamber to re-form the brass to the latter "improved" cartridges.

noun fire·arm \ˈfī(-ə)r-ˌärm\

  • small arms weapon, as a rifle or pistol, from which a projectile is fired by gunpowder.
  • A device which, on demand by activating some sort of switch like a trigger, ignites a very-rapidly burning propellant or an explosive, expels a projectile such as a bullet, or projectiles such as shot, from a tubular barrel (or barrels) with sufficient force as to cause acute bodily harm to the target, animal, or person which it hits.
  • A rifle, shotgun or handgun using gunpowder as a propellant. By federal definition, under the 1968 Gun Control Act. Air guns are not, by definition, firearms.
  • A volume of fire delivered by a military unit. Incorrectly used by the media to mean the ability of a small arm to be discharged many times without reloading.
Firing Line
  • A line, either imaginary or marked, from which people shoot their firearms down range.
  • The positions at which troops are stationed to fire upon the enemy or targets.
Firing Pin


  • The narrowly rounded, pointed component of a cartridge firearm that impacts and causes detonation of the primer. This may be mounted coaxially with a coil mainspring in a bolt rifle, may be a small replaceable tit mounted into the breech face of a sidelock break-open gun or an integral part of the [enclosed] hammer of a boxlock gun.
Firing Pin Block
  • A type of internal safety that prevents the firing pin from moving forward for any reason unless the trigger is pulled.
Five Screw Four Screw Three Screw
  • Terms relating to Smith & Wesson double-action revolvers. The five screws were four retaining the sideplate and one at the front of the triggerguard. From the introduction of the Hand Ejector in 1905, there were five screws. Then, around 1955 S&W deleted the top sideplate screw. Around 1961, they deleted the triggerguard screw. Collectors find cheapening of fine products irritating. Consequently, all other things being equal, with Smith & Wesson revolvers, the more screws, the better.
Fixed Ammunition
  • A complete cartridge of several obsolete types and of today's rim fire and center-fire versions.


  • The tendency for blue finish to deteriorate into rust, seemingly without either wear or ill treatment. Winchester Model 1892 receivers are particularly vulnerable to this defect. But, at least the condition indicates that, almost certainly, the remaining finish at least is original.


  • A cartridge with a pronounced rim at the base. While not as easy-feeding in a repeating firearm as a rimless cartridge, far more reliably extracting in a break-open firearm particularly important in a heavy double rifle for use against big game that might fight back.
Flash Gap

(flăsh)  (găp)

The distance between the face of a revolver's cylinder and the breech end of the barrel. U.S. industry standards call for a gap of .006-inch, with a .003-inch tolerance in either direction. (The SAAMI advises that 0.012" is an industry maximum for revolver flash gap)

Flash Gap Tolerance
Flash Gap Tolerance














Flash Hider Flash Suppressor
  • A muzzle attachment intended to reduce visible muzzle flash caused by the burning propellant. Flash reducers lessen glare as seen by the shooter, but do not hide the flash from other observers to the front or side of the firearm.
Flash Pan
  • A tiny bowl-shaped vessel, attached to the side of a flint lock, to hold the priming charge of gunpowder, which in turn is protected from wind, rain and the adverse effects of gravity by the combination hinged frizzen-flashpan cover.
Flat Point Flat Nose
  • A bullet shape with a flat nose rather than a rounded one.
Flat Point Checkering
  • A traditional English style of checkering gunstocks whereby the diamonds are not brought to sharp points. While not offering as firm a grip as standard sharp point-pattern checkering, it is both more durable and allows the grain structure of the wood to show through better.
Fleur de Lys

[flur-dl-ee, -ees, floo r-; French flœr-duh-lees]

  • A design element used on the French royal coat of arms, a stylized lily flower, frequently appearing in the checkering designs of American custom rifles.
  • To jerk a firearm off target inadvertently at the instant of firing in timid anticipation of recoil.
  • Jerking the gun downwards just before the shot fires. Commonly caused by learning to shoot with a gun more powerful then they are ready for.
  • A hard, sedimentary, sub-micro-crystalline form of quartz, which when knapped (dressed to shape by chipping) and then struck against steel can be used to create sparks.
  • hard stone, a form of silica resembling chalcedony but more opaque,less pure, and less lustrous. a piece of this, especially as used for striking fire.


  • A system of firearms ignition, in general use circa 1660 - 1825, whereby the pull of a trigger releases a sear from a notch in a spring-loaded hammer, which holding a properly knapped piece of flint, strikes a vertical slab of steel (called a frizzen) scraping off tiny molten particles of the steel, and pushing it forward causes an integral flashpan cover to open forward, exposing a bit of fine gunpowder below, which when contacted by the falling sparks, ignites and sends a flash of fire through the touchhole, into the loaded breech setting off the main charge and firing the gun. The Flintlock system was supplanted by the Percussion system around 1820.
Floated Barrel
  • A rifle barrel mounted firmly to the receiver (which, in turn, is mounted firmly to the stock) but not touching the forend. Done so that the stock will not adversely effect accuracy by impinging upon the natural free vibration of the barrel when the rifle is fired.
Floating Firing Pin

[′flōd·iŋ] [′fīr·iŋ ‚pin]

On a revolver, a firing pin that is mounted inside the frame, as opposed to being pinned to the hammer. (A device used in the firing mechanism of a gun, mine, bomb, fuse, projectile, or the like, which strikes and detonates a sensitive explosive to initiate an explosive train or a propelling charge.)

Revolver with Floating Firing Pin
Revolver with Floating Firing Pin


















  • A cover, usually of metal, usually hinged and latched, on the bottom of a bolt action rifle action which, when opened, allows the internal magazine to be emptied.
Fluid Steel Barrels
  • Barrels made of homogeneous steel (not damascus steel) --- standard practice for over a century
Fluted Barrel
  • A rifle or pistol barrel, into which longitudinal grooves have been milled. Fluted barrels, while more expensive to make than round barrels, dissipate heat more rapidly and they provide a better stiffness-to-weight ratio.
Fluted Comb
  • A carved detail at the point of the comb, a concave groove for more graceful aesthetics, and to allow a more clearance for a more comfortable position for the thumb as it wraps over the wrist than does a fatter, non-fluted comb.


  • Stands for Full Metal Jacketed. A bullet completely enclosed (except for the base) in a hard metal jacket (usually an alloy of copper, sometimes a mild steel). This is the only type of bullet permitted in warfare.
  • A type of round in which in which the lead core bullet is encased in a harder metal jacket on the front and sides.
FMJ Bullets
FMJ Bullets


















Folding Stock
  • A long gun stock that may be doubled over for conveniently compact storage.
Follow Through
  • Holding the trigger to the rear after the shot has fired, until the sights are back on target, at which time the trigger is released.
  • A smooth, sometimes contoured plate, within a magazine, at the top of a spring, across which cartridges slide when being loaded into a chamber.
Forcing Cone

[′fȯrs·iŋ ‚kōn]

  • The portion at the breech of a revolver's barrel that tapers into the rifling. Tapered beginning of the lands at the origin of the rifling of a gun tube; the forcing cone allows the rotating band of the projectile to be gradually engaged by the rifling, thereby centering the projectile in the bore.
Revolver Forcng Cone
Revolver Forcing Cone


















  • One of the three major dismountable components of a break-open gun (the others being the barrel(s) and the action/buttstock) which secures the barrels to the receiver, often houses the ejector mechanism, and for some, provides a handle for the one's secondary hand.

  • That part of the stock forward of the action and located below the barrel or barrels. It is designed to give the shooter a place to hold the front end of the gun and protects the shooter's hand from getting burned on the hot barrel.
Forend Iron
  • The steel skeleton of the forend, into which any moving parts are fitted and which mates to and revolves about the action knuckle when the gun is opened.
  •  The gritty residue that cleaned out of the barrel and all areas of the firearm in order to clean it.
Fouling Shot
  •  A shot fired in a clean rifle barrel to put the barrel into the normal slightly dirty state from which it is fired. Often, a rifle will shoot to a different point of aim with this shot as compared to the subsequent shots.
Four Rules Of Firearm Safety
  • The four universal rules of firearms safety, which apply every single time a firearm is handled in any way or for any reason.

  • Rule One: All guns are always loaded.
  • Rule Two: Never point your firearm at anything you are not willing to destroy.
  • Rule Three: Never put your finger on the trigger unless your sights are on target.
  • Rule Four: Be sure of your target and what is behind it.

Stands for "feet per second," by which bullet velocity is measured. The foot per second (plural feet per second) is a unit of both speed (scalar) and velocity (vector quantity, which includes direction). It expresses the distance in feet (ft) traveled or displaced, divided by the time in seconds (s, or sec). The corresponding unit in the International System of Units (SI) is the metre per second.

Feet Per Second Ballistic Chart Feet Per Second Ballistic Chart

  • The common part of a handgun to which the action, barrel and grip are connected.
French Casing
  • A style of gun case, where all the cased components---barrels, action and accessories are fitted into shaped compartments with no space around them. An alternative to English Casing whereby all the cased components are secured into more open box-like compartments---the barrels and action secured well enough, but the accessories liable to moving around a bit.
French Gray
  • An acid etched or phosphate finish, applied typically to shotgun actions, forming a gray-colored, non-reflective matte finish which also provides some protection from rust. Also called, gray-etched.
  • That part of a flintlock action that receives the blow of the flint-tipped hammer, which then yields tiny molten fragments of steel---sparks---which fall into the flashpan, igniting the priming charge and thence, through the touchhole, the main charge
Front Sight
  • The front sight is placed at the muzzle end of the barrel. It is often (but not always) in the form of a dot or a blade. To attain a proper sight picture and shoot with the greatest degree of accuracy, the shooter's eye should be focused sharply upon the front sight while shooting, allowing both the rear sight and the target to blur somewhat.
  • Front, metal, part of a handgun's grip, which together with the backstrap, provides a mounting frame for the grip panels.
  • The part of a revolver or pistol grip frame that faces forward and often joins with the trigger guard.
Full Stock
  • A rifle or carbine with a one-piece stock extending to the muzzle. Sometimes called a Mannlicher stock, although such a term is confusing because Mannlicher Schoenauer rifles are built with both full and half stocks. Traditional in Europe for close-range woodland hunting, but not noted for extreme, long-range accuracy.
Funeral Grade
  • A colloquial term to describe a break-open gun, of any quality but often of the very highest, bearing the least possible decoration; having an all-blued receiver with either no engraving at all or only a simple borderline.
  • In British-speak, the visible small steel parts of a double gun: top lever, trigger guard, safety tab, forend release lever, etc. These parts are normally blued.