A painting from artist Frederick Coffay Yohn depicts Continental Army Brig. Gen. Nicholas Herkimer and his men fighting the British and Hessians at the Battle of Oriskany in New York, Aug. 6, 1777. Credit:Courtesy photo. VIRIN:260306-O-D0439-9004

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Operating in small shops, they created American-made, handcrafted rifles, pistols and muskets.  

While some parts were imported, gunsmiths often made complete firearms from scratch, including custom iron barrels and wooden stocks. Each gun was hand-filed and fitted, making every weapon a unique, one-of-a-kind piece.  

Unlike the guns of today, parts were not interchangeable, a huge drawback. Soldiers could not cannibalize parts from broken weapons on the battlefield to fix their own. Because parts were hand-forged and unique to each gun, there was no quick fix for a broken internal part. 

Only bore size, aka caliber, was somewhat standardized so that soldiers could use the same size lead balls.

In the heat of battle, black powder residue called fouling, broken flints, or mechanical failures would often render a significant percentage of a unit's muskets useless after just a few shots. A flash in the pan occurred when the priming powder in the external pan ignited, but the spark failed to travel through the main charge in the barrel. This resulted in the gun making a puff of smoke but not firing. Flints typically lasted for only 20 to 30 shots before they became too dull to produce a spark. The hammer would strike the steel, but no spark would fall into the powder. 

Black powder is highly sensitive to moisture. Even high humidity could turn the powder into useless sludge. The flint would spark, but the damp powder would fail to catch fire. The heavy spring that drives the hammer forward was under immense tension. If it snapped, the hammer would simply hang loose, making the weapon completely inoperable. Sear spring failure is the smaller internal spring holding the hammer at half-cock safety or full-cock, ready to fire. If it broke, the gun might fire prematurely or fail to stay cocked. 

The wooden stock was thinnest at the wrist where the soldier grips it. Dropping the gun or using it too forcefully in a bayonet charge often caused the wood to splinter or snap entirely. Broken hammers were often a weak point and could shear off at the neck after repeated use. If the gun's firing mechanism broke, it was still an effective 5-foot spear with the bayonet affixed. 

A gunsmith was as much a craftsman as a manufacturer. They had to be capable carpenters, blacksmiths and engravers to produce their rifles. A single rifle could take weeks or even months to make, depending on the desired quality and access to needed materials. Wood was plentiful in the dense forests of Colonial America, but materials like steel and the proper tools had to be obtained from cities or even Europe.

In most cases, a master gunsmith would have several apprentices who would spend years learning the trade. Once they were deemed sufficiently trained, usually after completing a weapon entirely by themselves, the apprentice would craft a set of their own tools based on the master's and set up their own shop.

The most difficult, but most valued, step was rifling the barrel. Rifling is spiral grooves inside the barrel. It increases the ball's range and accuracy. While this was done by hand with a specialized drill at first, later gunsmiths were aided by the invention of rifle-boring machines, which greatly eased the process.

Until the Industrial Revolution of the late-1800s, the gun manufacturing process remained largely the same. The advent of interchangeable parts increased gun manufacturing as pieces could be made individually and replaced as needed. Parts could also be swapped, meaning a person could have two barrels for the same gun and switch them as they needed.

Prior to this, if a gun was damaged, the gunsmith would often need to spend days crafting a replacement piece specifically for that weapon. Now parts are stamped from sheets of metal or cast into molds that can be used repeatedly. This ability to produce intricate, delicate mechanisms from tiny, machined parts enabled the invention of automatic firearms.

Modern soldiers carry spare parts, cleaning kits, firing pins and other supplies. Revolutionary War soldiers carried almost nothing for repairs except extra flints. 

A modern armorer maintains and repairs firearms with factory-provided parts, ensuring the unit's weapons meet technical standards for combat readiness.  A gunsmith is a skilled artisan capable of everything an armorer does, as well as custom fabrication and machining.