Skelp (sometimes spelled scelp) is
wrought iron
Wrought iron is an iron alloy with a very low carbon content (less than 0.05%) in contrast to that of cast iron (2.1% to 4.5%), or 0.25 for low carbon "mild" steel. Wrought iron is manufactured by heating and melting high carbon cast iron in an ...
or
steel
Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...
that is
rolled or
forged
Forging is a manufacturing process involving the shaping of metal using localized compression (physics), compressive forces. The blows are delivered with a hammer (often a power hammer) or a die (manufacturing), die. Forging is often classif ...
into narrow strips and ready to be made into
pipe or
tubing by being bent (into a
cylindrical shape) and
welded. The word is most commonly used in the traditional terminology of
smithing
A metalsmith or simply smith is a craftsperson fashioning useful items (for example, tools, kitchenware, tableware, jewelry, armor and weapons) out of various metals. Smithing is one of the oldest metalworking occupations. Shaping metal with a ...
and in the
iron
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's o ...
and
steel
Steel is an alloy of iron and carbon that demonstrates improved mechanical properties compared to the pure form of iron. Due to steel's high Young's modulus, elastic modulus, Yield (engineering), yield strength, Fracture, fracture strength a ...
industries. Before the 20th century, the welding was likely to be
forge welding
Forge welding (FOW), also called fire welding, is a solid-state welding process that joins two pieces of metal by heating them to a high temperature and then hammering them together. It may also consist of heating and forcing the metals together ...
. In the 20th and 21st centuries, it has been likelier to be
arc welding
Arc welding is a welding process that is used to join metal to metal by using electricity to create enough heat to melt metal, and the melted metals, when cool, result in a joining of the metals. It is a type of welding that uses a welding power ...
or
gas welding
Principle of burn cutting
Oxy-fuel welding (commonly called oxyacetylene welding, oxy welding, or gas welding in the United States) and oxy-fuel cutting are processes that use fuel gases (or liquid fuels such as gasoline or petrol, diesel, bio ...
.
In the context of traditional
gunsmith
A gunsmith is a person who repairs, modifies, designs, or builds guns. The occupation differs from an armorer, who usually replaces only worn parts in standard firearms. Gunsmiths do modifications and changes to a firearm that may require a very ...
ing, one way to make
gun barrel
A gun barrel is a crucial part of gun-type weapons such as small arms, small firearms, artillery pieces, and air guns. It is the straight shooting tube, usually made of rigid high-strength metal, through which a contained rapid expansion of high ...
s has been to make them from skelp, like one would make other pipe or tubing. Barrels made from skelp have typically been thought of as having inferior
quality
Quality may refer to:
Concepts
*Quality (business), the ''non-inferiority'' or ''superiority'' of something
*Quality (philosophy), an attribute or a property
*Quality (physics), in response theory
*Energy quality, used in various science discipli ...
. (Pipe made from skelp can be perfectly acceptable in quality, but a gun barrel must withstand much higher
pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and eve ...
s than most pipes.) Cheap gun barrels could be made this way in the Damascus method—wrapping the skelp around a
mandrel
A mandrel, mandril, or arbor is a tapered tool against which material can be forged, pressed, stretched or shaped (e.g., a ring mandrel - also called a triblet - used by jewellers to increase the diameter of a wedding ring), or a flanged or t ...
to make
spiral
In mathematics, a spiral is a curve which emanates from a point, moving further away as it revolves around the point. It is a subtype of whorled patterns, a broad group that also includes concentric objects.
Two-dimensional
A two-dimension ...
s which were then
hammer
A hammer is a tool, most often a hand tool, consisting of a weighted "head" fixed to a long handle that is swung to deliver an impact to a small area of an object. This can be, for example, to drive nail (fastener), nails into wood, to sh ...
ed and forged into a tube. The mandrel was then removed, the interior
reamed, and the exterior
filed until a finished tube was complete. The tube was then
polished and
breeched.
This method of
fabrication was used because it was difficult to
cast
Cast may refer to:
Music
* Cast (band), an English alternative rock band
* Cast (Mexican band), a progressive Mexican rock band
* The Cast, a Scottish musical duo: Mairi Campbell and Dave Francis
* ''Cast'', a 2012 album by Trespassers William ...
a solid barrel and then
drill
A drill is a tool used for making round holes or driving fasteners. It is fitted with a drill bit for making holes, or a screwdriver bit for securing fasteners. Historically, they were powered by hand, and later mains power, but cordless b ...
it out without the
bit coming out the side. In many regions and eras, especially before the 20th century, gunsmithing has been achieved without the help of advanced
machine tool
A machine tool is a machine for handling or machining metal or other rigid materials, usually by cutting, Boring (manufacturing), boring, grinding (abrasive cutting), grinding, shearing, or other forms of deformations. Machine tools employ some s ...
practice, such as
gun drill
Gun drills (through coolant drill) are straight fluted drills which allow cutting fluid (either compressed air or a suitable liquid) to be injected through the drill's hollow body to the cutting face. They are used for deep hole drilling—a ...
ing or advanced
boring methods. In such contexts, advanced smithing and filing skills have often made up for the lack of machine tools.
Damascus barrels were generally designed for
black powder
Gunpowder, also commonly known as black powder to distinguish it from modern smokeless powder, is the earliest known chemical explosive. It consists of a mixture of sulfur, charcoal (which is mostly carbon), and potassium nitrate, potassium ni ...
charges. The breech end of the tube was much thicker than the
muzzle end, and this held the initial impulse pressure from the black powder. By the time the
bullet
A bullet is a kinetic projectile, a component of firearm ammunition that is shot from a gun barrel. They are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax; and are made in various shapes and constru ...
reached the muzzle, the pressure had dropped quite a bit, so muzzle reinforcement was not needed. This gave a better weight distribution through the length of the weapon.
Smokeless powder
Finnish smokeless powder
Smokeless powder is a type of propellant used in firearms and artillery that produces less smoke and less fouling when fired compared to black powder. Because of their similar use, both the original black powder formula ...
s burn more slowly than black powder, thus maintaining high pressures throughout the barrel. Since the barrel is not reinforced at the muzzle, it may not be able to contain the pressure. Also, most Damascus barrels were made before modern smokeless powders, so the age of the barrel can be a
safety hazard
A hazard is a potential source of harm. Substances, events, or circumstances can constitute hazards when their nature would potentially allow them to cause damage to health, life, property, or any other interest of value. The probability of that ...
.
Bibliography
* Russell, Carl P. (1957). ''Guns on the early frontiers: a history of firearms from colonial times through the years of the Western fur trade''. Berkeley, CA, USA: University of California Press. .
References
{{reflist
External links
Damacus Twist Barrels information
Firearm construction
Metal forming