is a person who repairs, modifies, designs, or builds firearm
A firearm is a weapon that launches one, or many, projectile at high velocity through confined burning of a propellant. This subsonic burning process is technically known as deflagration, as opposed to supersonic combustion known as a detonation. In older firearms, the propellant was typically...
s. This occupation is different from an armorer. The armorer primarily maintains (disassembly, cleaning) weapons and limited repairs involving parts replacement and possibly work involving accurization. A gunsmith does factory level repairs, renovation (such as applying metal finishes), and makes modifications and alterations for special uses. In Gunsmithing you can as well carve or paint designs in the gun when you get finished with the work.
Gunsmiths may be employed in:
- factories by firearms manufacturers,
An armory or armoury is a place where arms and ammunition are made, maintained and repaired, stored, issued to authorized users, or any combination of those...
by military or law-enforcement agencies,
- sporting goods stores, or
- small gunsmith shops, as either the owner, or as one of a handful of employees.
To pursue the entirety of this trade, a gunsmith must possess skills as a mechanic
A mechanic is a craftsman or technician who uses tools to build or repair machinery.Many mechanics are specialized in a particular field such as auto mechanics, bicycle mechanics, motorcycle mechanics, boiler mechanics, general mechanics, industrial maintenance mechanics , air conditioning and...
, a metalworker, a woodworker, and an artisan
An artisan is a skilled manual worker who makes items that may be functional or strictly decorative, including furniture, clothing, jewellery, household items, and tools...
; be knowledgeable in shop mathematics, ballistics
Ballistics is the science of mechanics that deals with the flight, behavior, and effects of projectiles, especially bullets, gravity bombs, rockets, or the like; the science or art of designing and accelerating projectiles so as to achieve a desired performance.A ballistic body is a body which is...
, and chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....
; and be capable of working accurately and precisely. Those who are (self-)employed in small gunsmith shops must also possess skills as small business
A small business is a business that is privately owned and operated, with a small number of employees and relatively low volume of sales. Small businesses are normally privately owned corporations, partnerships, or sole proprietorships...
operators; work effectively with a wide variety of customers; and remain abreast of, and comply with federal
The federal government of the United States is the national government of the constitutional republic of fifty states that is the United States of America. The federal government comprises three distinct branches of government: a legislative, an executive and a judiciary. These branches and...
, state, and local laws, ordinances, and requirements.
Due to the great breadth of subject matter to be mastered, many gunsmiths specialize in only a few of the skills required of the general gunsmith. Alternatively, some gunsmiths learn many of the skills of the trade, but only apply them to a few weapon types (e.g. only pistols, only shotguns, only specific brands or models).
In many countries of the world, the possession and ownership of firearms by civilians is highly restricted or outright illegal (see Gun law
A gun law is a law that pertains to firearms. Restrictions on gun ownership and use vary greatly both by country and the type of firearm used....
s). The practice of gunsmithing is therefore typically restricted. The only firearms-related repairs are by individuals trained and employed by the military or police. These individuals are known as Armorers. Typically, their skill level is usually far below that of the artisan Gunsmith. Where the Gunsmith frequently has to design, manufacture and fit parts ranging from small internal parts and assemblies, the Armorer usually only has to replace standard interchangeable parts
Interchangeable parts are parts that are, for practical purposes, identical. They are made to specifications that ensure that they are so nearly identical that they will fit into any device of the same type. One such part can freely replace another, without any custom fitting...
belonging to only one type, series, or family of military-related firearms. They typically are furnished a large inventory of standard parts that are known to wear and cause malfunctions
A firearm malfunction is the partial or complete failure of a firearm to operate as intended. Malfunctions range from temporary and relatively safe situations, such as a casing that didn't eject, to potentially dangerous occurrences that may permanently damage the gun and cause injury or death...
in the "weapons" they will encounter, and they are simply trained to replace these items until satisfactory function is restored.
Armorers are usually employees of military and law-enforcement institutions, and may be officers of these agencies that perform these repairs as part of their official duties. Their repairs usually only on the weapons and weapon systems that are the official property of these institutions, and limited to restoring these government-owned firearms to officially sanctioned standards of functionality and configuration.
In the regions where ownership is permitted but very limited and highly restricted to those individuals able to afford the high costs of acquiring and owning a firearm despite the expense, those firearms that are allowed tend to be fewer in number, but with levels of craftsmanship and decoration that approach that of an art object instead of simply a device to expel a projectile. Gunsmithing in these regions (as in Germany and Britain) is concerned with the hand crafting of completely custom-made firearms, tailored to the requirements of the owner, and the expense of this type firearm can exceed that of a typical residential dwelling.
Germany has a tradition of hunting, but this is generally a very expensive undertaking that limits its participation to the "well-heeled and Noble". Firearms possession is highly regulated by the Police, and most hunters have only one long gun, and perhaps one pistol. This has led to the development of "Drilling," a multi-barrel gun that may incorporate a double-barreled shotgun above with a high-powered single-shot barrel below. These typically have highly sophisticated breech mechanisms, precise fitting, and are hand-engraved by artists specializing in this work. The stocks are usually fitted to the individual and are very expensive wood with highly figured grain.
England makes some of the most expensive hand-crafted firearms in the world, despite a highly restrictive ownership environment. But, as the Gunsmith's patrons are usually well able to afford the high ownership fees and stringent storage requirements, the price of the arm is only secondary. Decoration of these arms, typically double-barreled shotguns, is on par with the plates used to mint currency and is priced about the same. Several of the other European countries follow this pattern, as in Italy, where the art of the Gunsmith has also reached a high level of sophistication. These craftsmen may specialize as in the case of the Gun Engraver and Stockmaker. Generally, these craftsmen-artists serve long apprenticeships under Master Gunmakers. They may also be members of Guilds which sets up apprentice programs (often sponsored by the Governments in these countries as highly crafted firearms are important items in the export trade), supervise training, and conduct exams where the Journeyman-level Gunsmiths submit sample firearms of their own work in order to be admitted the Guild membership. Many of these artists can only be regarded as "Gunmakers" instead of Gunsmiths, and do repairs only on the very highest grade firearms. Many are able to make substantial livelihood. Many women also participate in these firms, with some of the most exquisite engraving decoration originating as their work.
United States of America
In the United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
, the Bureau of Alcohol, Tobacco, Firearms and Explosives
The Bureau of Alcohol, Tobacco, Firearms and Explosives is a federal law enforcement organization within the United States Department of Justice...
(ATF) is the primary federal agency
Federal agency may refer to:*United States federal agencies—see List of United States federal agencies*Federal agency -See also:*Government agency*Statutory corporation*Statutory Agency*Crown corporation*Government-owned corporation...
overseeing all legitimate businesses that deal with firearms. The ATF is in charge of the licensing of all legitimate firearms dealers and Gunsmiths in the US that engage in business with the public. The issuance of a Federal Firearms License (FFL
A Federal Firearms License is a license that enables an individual or a company to engage in a business pertaining to the manufacture of firearms and ammunition or the interstate and intrastate sale of firearms...
) involves a thorough background investigation and an inspection of the Gunsmith's premises by an Agent of the ATF. The fee for a FFL is currently $200.00 (for 3 years). The ATF requires all gunsmiths to record all repairs, noting the serial numbers, type of firearm, caliber or gauge, and full particulars of the owner, with an accepted form of Identification ID to be presented and recorded in the records. Gunsmiths are required to maintain these records in a permanent, non-alterable form.
The ATF inspects the premises of all licensed gunsmiths, with unannounced visits at periodic intervals. The ATF is granted the power by the US Government to initiate the prosecution in US Federal Court of gunsmiths that wilfully omit or violate these provisions. Punishment can range from losing their FFL (and therefore the privilege to engage in any firearms-related business), to fines and in severe cases, such as conspiring to supply the criminal element with black market weaponry, imprisonment in a Federal prison.
Gunsmiths who lack sophisticated machine shop capabilities must understand the law. Enlisting an unlicensed (no FFL) machine shop to create gun receivers
In firearms terminology, the receiver is the part of a firearm that houses the operating parts. The receiver usually contains the bolt carrier group, trigger group, and magazine port. In most handguns, the receiver, or frame, holds the magazine well or rotary magazine as well as the trigger mechanism...
can be illegal. Other common parts such as grips, barrels, triggers, sights, magazines, recoil springs, and stocks can be manufactured freely, but all receiver development work does require licensing..
Generally, gunsmiths cannot undertake the repair of a firearm they believe is illegally held by a person not permitted to own a firearm (a convicted felon, for instance) or one that otherwise violates the laws in which the owner resides. The ownership of firearms in the US is governed by local laws. These laws and regulations vary greatly from state
A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...
to state, county
In the United States, a county is a geographic subdivision of a state , usually assigned some governmental authority. The term "county" is used in 48 of the 50 states; Louisiana is divided into parishes and Alaska into boroughs. Parishes and boroughs are called "county-equivalents" by the U.S...
to county, city
A city is a relatively large and permanent settlement. Although there is no agreement on how a city is distinguished from a town within general English language meanings, many cities have a particular administrative, legal, or historical status based on local law.For example, in the U.S...
to city, and potentially across all jurisdictional lines.
These laws may also vary by:
- firearm type (handgun? longarm? rifle? shotgun?)
- firearm model (semi-automatic? full automatic? caliber?)
- intended modification (minimum barrel length? magazine size? fully automatic?)
- customer or recipient (legal owner? felon? background check?)
- quantity of firearms (how many per week? per month?)
The primary technical
responsibility of gunsmiths is to ensure that the weapons they work on function safely.
They accomplish this firstly by always properly observing gun safety
Gun safety is a collection of rules and recommendations that can be applied when handling firearms. The purpose of gun safety is to eliminate or minimize the risks of unintentional death, injury or damage caused by improper handling of firearms....
handling procedures: both in their own actions, and in the actions of their customers and the people around them.
They accomplish this secondly by inspecting firearms to ensure safe mechanical operation. Gunsmiths use their in-depth knowledge of firearms to guide these inspections: either repairing deficiencies; or notifying customers of unsafe conditions and taking steps to prevent catastrophic failures.
Some of the ways that even properly handled firearms can fail and endanger their users and those around them are:
- Improper Assembly
- Missing Parts
- Cracks: all cracked parts are cause for concern, but especially so in the chamber-area, bolt, bolt-lugs, or buttstock.
- Bore Obstructions: being either dented or bent barrels, or foreign material in barrels.
- Improper Headspace: dimensions concerning the relative locations of the chamber and the bolt are not within specified tolerances.
- Improper Timing: (applies to fully automatic firearms and revolvers).
- Safety-Mechanism Malfunctions: potentially allowing a firearm with the safety mechanism supposedly engaged to unexpectedly fire.
- Worn Sear Edges: potentially allowing a firearm to unexpectedly fire when the safety mechanism is disengaged.
- Firing-Pin Tips Deformed: leading to the possibility of primer-rupture.
This list is not comprehensive. Many failure modes are dependent on the particular model of firearm.
(listed in approximate, but not exact, order of increasing difficulty)
- Keep records of all customers, firearms, and transactions to satisfy ATF
The Bureau of Alcohol, Tobacco, Firearms and Explosives is a federal law enforcement organization within the United States Department of Justice...
requirements, though this doesn't apply to pre-1898 models, which are considered antiques rather than firearms.
- Disassemble, clean, inspect, lubricate & reassemble.
- Remove corrosion and touch-up finish.
- Repair burred or damaged parts with files & stones.
- Replace defective parts with factory-made replacements, hand-fitting as necessary.
- Add after-market customizations:
- grip caps
- butt plates
- Repair and re-finish wooden stock parts.
- Checker or re-checker grip areas.
- Deepen or clean up worn or damaged engravings & markings.
- Re-crown damaged muzzles on a lathe.
- Repair dented shotgun barrels.
- Install (solder) or repair rib on shotgun barrels, or repair double-barrel assemblies.
- Measure & correct head-space dimensions.
- Check for excessive bore erosion.
- Troubleshoot and repair feeding, ejecting & firing problems.
- Test-fire firearms with conventional loads to ensure proper operation.
- Fabricate wooden stocks to customer specifications and body dimensions. Fit same to existing receiver and barrel.
- Glass-bed actions to stocks to improve accuracy.
- Remove existing metal finish, and re-blue metal parts.
- Fabricate replacement parts from metal stock.
- Modify trigger-pull weight through careful stoning of trigger mechanism parts.
- Fire proof-loads
A proof test is a test wherein a deliberately over-pressured round is fired from a firearm in order to verify that the firearm is not defective and will not explode on firing. The firearm is inspected after the test, and if it is found to be in sound condition, then it is marked with a proof mark...
through weapons to insure sufficient strength of parts under over-load conditions.
- Replace worn barrels, which have fired so many rounds that they are no longer of the specified caliber (which leads to loss of accuracy).
- Change caliber or cartridge of existing rifle, by changing barrel, and modifying receiver.
- Re-cut rifling and change caliber of existing barrel.
- Design and build complete rifles by fitting stock barrels to stock receivers; fabricating or purchasing additional parts as needed, and fitting same to rifle. Fitting custom stock to same.
- Design and build a complete rifle starting with several pieces of blank steel and a slab of walnut; using nothing more than a lathe, saws, files, chisels, & rasps.
While some gunsmiths are general practitioners in this trade, some of the more important specializations are:
Builds guns to customer's specification, from raw materials and shelf parts. Called upon by professional target-shooters to create highly accurate custom rifles. Likely the most highly skilled of gunsmiths, as they are required not only to have proficiency in the other areas of gunsmithing, but must also be well educated in machining
Conventional machining is a form of subtractive manufacturing, in which a collection of material-working processes utilizing power-driven machine tools, such as saws, lathes, milling machines, and drill presses, are used with a sharp cutting tool to physical remove material to achieve a desired...
, in order to manufacture the individual components and springs before assembly takes place.
Applies various chemical processes (browning, bluing
Bluing is a passivation process in which steel is partially protected against rust, and is named after the blue-black appearance of the resulting protective finish. True gun bluing is an electrochemical conversion coating resulting from an oxidizing chemical reaction with iron on the surface...
Parkerizing is a method of protecting a steel surface from corrosion and increasing its resistance to wear through the application of an electrochemical phosphate conversion coating...
, among others) to the metal parts of guns to develop corrosion resistant surface layers on the steel. Cyanide case hardening
Case hardening or surface hardening is the process of hardening the surface of a metal, often a low carbon steel, by infusing elements into the material's surface, forming a thin layer of a harder alloy...
is a combined chemical and heat-treatment process which develops mottled tempering colors on steel surfaces: greatly valued for their appearance. Typically, its use is usually restricted to receivers, rarely barrels. Although providing corrosion resistance, the colored surface layers are subject to wear: antique firearms for sale frequently stating what specific percentage of the factory original case coloring remains.
Carves gun stocks from wood (usually walnut; although birch, maple, and apple wood, among others, are frequently seen). Fits stocks to the metal parts of the gun (receiver and barrel), as well as to customer's body dimensions. The form of stocks are executed using saw
A saw is a tool that uses a hard blade or wire with an abrasive edge to cut through softer materials. The cutting edge of a saw is either a serrated blade or an abrasive...
A chisel is a tool with a characteristically shaped cutting edge of blade on its end, for carving or cutting a hard material such as wood, stone, or metal. The handle and blade of some types of chisel are made of metal or wood with a sharp edge in it.In use, the chisel is forced into the material...
s, gouges, rasp
A rasp is a tool used for shaping wood or other material. It consists of a point or the tip, then a long steel bar or the belly, then the heel or bottom, then the tang. The tang is joined to a handle, usually made of plastic or wood. The bar has sharp teeth...
s, and file
A file is a metalworking and woodworking tool used to cut fine amounts of material from a workpiece. It most commonly refers to the hand tool style, which takes the form of a steel bar with a case hardened surface and a series of sharp, parallel teeth. Most files have a narrow, pointed tang at one...
s. The surfaces are then finished by sanding, scraping
Scraping is a live album from Calexico's January 2002 concert in San Francisco's Great American Music Hall.The recording features several songs with the mariachi Luz De Luna.-Track listing:# "Wash"# "The Ride "# "Sonic Wind"...
A stain is a discoloration that can be clearly distinguished from the surface, material, or medium it is found upon. Stains are caused by the chemical or physical interaction of two dissimilar materials...
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....
ing, or lacquer
In a general sense, lacquer is a somewhat imprecise term for a clear or coloured varnish that dries by solvent evaporation and often a curing process as well that produces a hard, durable finish, in any sheen level from ultra matte to high gloss and that can be further polished as required...
(This specialization is frequently combined with that of the Stockmaker) Uses checkering tools to create an ornate pattern of small raised diamonds in the wood surfaces which are to be gripped. The checkering tools are in effect tiny saws, designed to leave a v-shaped groove (of approximately 60 to 90 degrees) in the surface of the wooden gunstock. Special checkering tools consisting of two saw blades in parallel are used to set the spacing (between 16 to 24 lines per inch). The area to be checkered is covered by one set of such grooves parallel to each other. A second set of parallel grooves is then executed across the first set, at approximately a 30 degree angle, leaving the area covered with small pointed diamonds. The edges of the checkered area are frequently ornamented with simple bas-relief wood carving, frequently variations on the fleur-de-lis
The fleur-de-lis or fleur-de-lys is a stylized lily or iris that is used as a decorative design or symbol. It may be "at one and the same time, political, dynastic, artistic, emblematic, and symbolic", especially in heraldry...
Uses hand-gravers or die-sinker's chisels to cut designs or pictures into the metal surfaces of the gun, primarily the receiver. Pneumatically driven engraving systems, such as the Gravermeister, developed by GRS Tools, may be used to replace or supplement hand-powered engraving. Other metals (especially gold and silver) may be inlaid and engraved to further the design. Designs usually consist of elaborate scroll-work based upon Acanthus
The acanthus is one of the most common plant forms to make foliage ornament and decoration.-Architecture:In architecture, an ornament is carved into stone or wood to resemble leaves from the Mediterranean species of the Acanthus genus of plants, which have deeply cut leaves with some similarity to...
leaves or vines, or may be of purely abstract spirals. The pictures are usually of game animals or birds, and hunting dogs. Before the development of corrosion resistant surface treatments for steel, gun surfaces were engraved to retain more oil to prevent rust. In modern usage, guns are engraved purely for artistic reasons. Top grade engraving may add significantly to the value of quality firearms.
Specializes in work on pistols and revolvers. Pistolsmiths should be proficient in a range of skills such as woodworking, checkering, machining, metal finishing and metalworking. They must have an excellent understanding of the mechanical characteristics and function of the guns they work on. Often a pistolsmith is called on for extensive customization of a handgun. A good pistolsmith can turn a poorly constructed firearm into one that looks and handles much better.
Some gunsmiths used their experience and skills to become small-operation manufacturers, specializing in making only a few types of gun parts, for sale to other gunsmiths and gunmakers. Some of the more important part categories are:
- trigger assemblies
- locks (as in 'flint-locks')
Training and education
In general, gunsmiths develop and expand their skills through years of experience.
Some common ways to get started in gunsmithing include:
- Attending one of the well-known schools offering training in the trade.
- Community colleges and correspondence courses offer various courses of study (less than two years long) leading to a degree or a certification.
- Military Training:
- The U.S. Army trains and employs MOS
A United States military occupation code, or a Military Occupational Specialty code , is a nine character code used in the United States Army and United States Marines to identify a specific job. In the U.S. Air Force, a system of Air Force Specialty Codes is used...
45B – Small Arms Repairmen. (was redesignated MOS 91F in Spring of 2004)
- The U.S. Air Force trains and employs Combat Arms Instructors (Firearms instructors and small arms repairers)AFSC(MOS) 3P0X1B.
- The U.S. Marine Corps trains and employs MOS 2111 and MOS 2112.
- The U.S. Navy trains and employs Gunner's Mates (GM).
- Apprenticeships: learn directly from active gunsmiths. Talk with gunsmiths in your area, and offer your help around the shop in exchange for learning about this trade.
- The National Rifle Association
The National Rifle Association of America is an American non-profit 501 civil rights organization which advocates for the protection of the Second Amendment of the United States Bill of Rights and the promotion of firearm ownership rights as well as marksmanship, firearm safety, and the protection...
offers short courses in many common tasks and skills of professional gunsmithing.
A machinist is a person who uses machine tools to make or modify parts, primarily metal parts, a process known as machining. This is accomplished by using machine tools to cut away excess material much as a woodcarver cuts away excess wood to produce his work. In addition to metal, the parts may...
skills, while not limited to gunsmithing, are of great help to aspiring gunsmiths.
News of the most highly skilled and talented gunsmiths typically spreads by word of mouth, based on the quality of their work. The very best and most talented gunsmiths command premium prices for their services, and may have waiting lists booked for several years in advance.
Do-it-yourself gun making has been practiced by many people around the world. Especially in certain third-world countries as Afghanistan
Afghanistan , officially the Islamic Republic of Afghanistan, is a landlocked country located in the centre of Asia, forming South Asia, Central Asia and the Middle East. With a population of about 29 million, it has an area of , making it the 42nd most populous and 41st largest nation in the world...
The Republic of Yemen , commonly known as Yemen , is a country located in the Middle East, occupying the southwestern to southern end of the Arabian Peninsula. It is bordered by Saudi Arabia to the north, the Red Sea to the west, and Oman to the east....
and other countries in the Middle East
The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...
, diy-gunsmithing has become a necessary expediency.
- John Moses Browning, American firearms inventor. The designer of the Browning Automatic Rifle
The Browning Automatic Rifle was a family of United States automatic rifles and light machine guns used by the United States and numerous other countries during the 20th century. The primary variant of the BAR series was the M1918, chambered for the .30-06 Springfield rifle cartridge and designed...
and father of Val Browning.
- Jonathan Browning
Jonathan Browning was an American inventor and gunmaker. Born in Sumner County, Tennessee, he started earning a living as a blacksmith and later switched to become a lock and gunsmith. He invented a 'sliding breech' repeating rifle also called a Harmonica gun between 1834 and 1842 while living...
, the American pioneer and firearms inventor and father of John Moses Browning.
- Val A. Browning
Val Allen Browning was a noted Utah industrialist, philanthropist, and third generation gun innovator. His grandfather, Jonathan Browning, opened a gun shop in Ogden, Utah in 1852 and his father, John Browning, is considered by many to be the most important gun inventor in history.-Life:Born in...
, American firearms inventor.
- John Garand
John Cantius Garand was a designer of firearms best known for creating the first successful semi-automatic rifle to be widely used in active military service, the M1 Garand....
, Canadian-American firearms designer. Noted as the designer of the M1 Garand
The M1 Garand , was the first semi-automatic rifle to be generally issued to the infantry of any nation. Called "the greatest battle implement ever devised" by General George S...
- Dieudonné Saive
Dieudonné Joseph Saive was a Belgian small arms designer who designed the FN Model 1949 and the FN FAL. He became the head firearms developer of Fabrique Nationale after the death of John Browning. After John Browning's death, Saive continued with several projects for modernizing and improving...
, Belgian small arms designer who designed the FN Model 1949
The Fabrique Nationale Model 1949 is a semi-automatic rifle designed by Dieudonné Saive and manufactured by Fabrique Nationale...
and the FN FAL
The Fusil Automatique Léger or FAL is a self-loading, selective fire battle rifle produced by the Belgian armaments manufacturer Fabrique Nationale de Herstal . During the Cold War it was adopted by many North Atlantic Treaty Organization countries, with the notable exception of the United States...
- Eugene Stoner
Eugene Morrison Stoner is the man most associated with the design of the AR-15, which was adopted by the US military as the M16...
, American firearms designer. Noted as the designer of the AR-15
The AR-15 is a lightweight, 5.56 mm, air-cooled, gas-operated, magazine-fed semi-automatic rifle, with a rotating-lock bolt, actuated by direct impingement gas operation. It is manufactured with the extensive use of aluminum alloys and synthetic materials....
, later adopted as the M16 Rifle
The M16 is the United States military designation for the AR-15 rifle adapted for both semi-automatic and full-automatic fire. Colt purchased the rights to the AR-15 from ArmaLite, and currently uses that designation only for semi-automatic versions of the rifle. The M16 fires the 5.56×45mm NATO...