One of the best ways to investigate the field is to learn the proper use and care of firearms. Gun handling classes are offered by the National Rifle Association, YMCAs, 4-H Clubs, local hunting clubs, and sporting goods stores. Taking classes offered through the National Rifle Associations Short-Term Gunsmithing School Program (https://firearmtraining.nra.org/short-term-gunsmithing-school.aspx) is another way to discover whether you have an aptitude for gunsmithing before enrolling in a more extensive program. These courses range in length from several days to a week or two and are held at different community colleges and technical institutions. You must be at least age 18 to participate. 

You can also try to explore the career through a part-time or summer job with an independent gunsmith. Also check sporting goods and hunting stores or shooting ranges for employment opportunities.

Both long guns and handguns consist of three basic elements: the barrel, the stock, and the action or firing mechanism. The gunsmith assembles these parts according to blueprint orders or customer specifications. The pieces are usually made by parts manufacturers, although a gunsmith may make a piece for a special custom-made gun or for the restoration of an antique gun.

The gunsmith first takes the stock of the gun and attaches the barrel and the action to it. Then the parts are aligned properly. The gunsmith also attaches equipment, such as metallic or optical sights for aiming the gun, pistol grips, decorative pieces, and recoil pads to cushion the impact of the blast on the shooter.

Gun stocks are made by machine or cut by hand. Those that come from factories are often only partially completed, so the gunsmith can carve it to a perfect fit for the action and barrel being attached. The gunsmith finishes or polishes the gun stock with lacquers, oils, resins, or other finishing material. Hardwoods such as walnut and maple are most often used for stocks because of their beauty and durability. Often a gun owner will have the stock decorated and carved with designs, such as outdoor scenes or with a diamond pattern to improve the grip. The action and stock can also be engraved.

Gunsmiths also treat and protect the metal parts of the firearm by a process called "bluing." This gives the metal a rust-resistant surface and also imparts a bluish color to the metal. Certain gunsmiths become experts in bluing, and other gunsmiths may send their work to these specialists. Specialization in other aspects of the gunsmithing process is fairly common among practitioners.

Other gunsmithing tasks include reboring barrels to enlarge the caliber of the bore and cutting new rifling into the barrels of small firearms with a broaching machine. Custom work on firearms gives gunsmiths the chance to display their special skills. Often a hunter will come in with plans for a specially handmade rifle, and the gunsmith will make the rifle from blank factory pieces.

In addition to building and modifying firearms, gunsmiths also clean and repair guns. They restore antique guns that have historic or sentimental value. After assembling or repairing firearms, the gunsmith test-fires the pieces with proof loads to determine their strength, alignment, and proper assembly. Expert gunsmiths with an aptitude for machining and physics can design new guns by laying out plans on paper and calculating bullet-flight arcs, sight positioning, and other details.