| Bore |
The
bore is the tube, or inner portion of the gun barrel.
The name is also used to describe the diameter of
the same tube. The
bore of a gun is always a little larger than the diameter
of the roundshot (or cannonballs) used in the gun, to
prevent them being jammed inside the bore itself.
While most guns were classified using the weight of
the shot they fired (6-pounder for example), mortars and
howitzers were classified using the bore size.
From the early 20th century, most guns
started using the bore size for classification (14 inch
gun, 75mm howitzer and so on).
|
Breech
|
The
rear of the gun. To
be completely accurate, the breech (or “breech
chamber”) is the area inside the barrel right at the
end, where the powder is ignited.
|
Breech Ring
|
(Also
known as the base ring).
This is the band that circles the gun immediately
behind the vent. It
sometimes forms part of the cascabel.
Gun length is measured from the muzzle to the rear
end of the breech ring |
Button
|
The
knob at the rear of the cascabel or breech of the gun. |
Cascabel
|
(Sometimes
written as “Cascable”).
This was the whole part of the gun behind the base
ring. In
other words, it was the rear part of the breech of a gun. |
Dolphins
|
These
are the lifting handles (shaped like semi-circles) that
were sometimes fitted on the top of cannons, and were
mounted on the point of balance of the gun (running up and
down the barrel). This
was usually close to the trunnions.
Their name derives from their shape, as these
lifting handles were often cast in the shape of dolphins,
although sometimes serpents or even elephants were used. These
were almost exclusively reserved for bronze guns. |
Muzzle
|
The
muzzle of a gun is the front face containing the bore,
where the powder and shot are loaded on
“muzzle-loading” guns.
To be pedantic, the name is also used to refer to a
portion of the very front portion of the barrel if a
reinforcing ring known as a “muzzle astragal” is
present.
To
recap, “muzzle-loading guns” are loaded from the
front, and everything is rammed down the barrel.
“Breech-loading guns” are loaded from the back,
like a modern military piece of artillery.
While the earliest wrought-iron guns were
breech-loaders, these fell into disuse by the late 16th
century. Breech-loaders
were re-introduced in the late 19th century,
and quickly became the standard type of gun.
|
Pounder
|
Before
the mid 17th century, guns were classified by
names, such as “saker”, demi-culverin” and
“cannon”. Both
systems were used during the last half of the century, but
after around 1700, guns were classified by the size of
shot they fired: 6-pounder, 18-pounder and so on. |
| Reinforce |
The
back half of a gun barrel, from the trunnions back to the
breech ring. It
is reinforced by being thicker than the front part of the
gun. A series
of rings or bands sometimes augment this, and if used,
they are called reinforcing rings.
These are called the “first reinforcing ring”
(between breech and trunnions) and “second reinforcing
ring” (at the trunnions themselves). If a similar ring is used between the trunnions and the
muzzle, it is called the “muzzle astragal”.
If a ring is place just forward of the vent in
addition to the first reinforce ring, it is known as the
“vent field astragal”.
This
may sound confusing, but it gets worse.
If there are no reinforce rings between the
trunnions and the breech, the reinforce area is simply
called the reinforce.
If one ring divides it, it is split into two parts;
the “first reinforce” (nearer the breech) and the
“second reinforce” (nearer the trunnions).
If a “vent field astragal” astragal is added,
the area between it and the “base ring” is known as
the “vent field”.
To
confuse things even further, if the barrel in front of the
trunnions is divided by a “muzzle astragal”, the part
closest to the trunnions is called the “chase”, and
the part nearest the muzzle is referred to as
“muzzle”. The
muzzle also refers to the very front face of the gun.
|
| Shot |
The
solid projectiles fired from a cannon.
In most cases shot means “roundshot”; spherical
cast-iron cannon balls.
Other types include split-shot, bar-shot,
grapeshot, hailshot, spiked shot or cased shot, all with
their particular uses.
Contrary to Hollywood myth, shot doesn’t explode
on contact!
|
| Tompion |
This
is a plug inserted into the muzzle of the gun to keep it
dry when not in use.
|
| Touch-Hole |
See
“Vent”
|
| Trunnion |
The
cylinders or tabs of solid metal which project from each
side of the cannon. They
are designed to rest in slots in the gun carriage, and
support the gun in place on the gun carriage.
They are also the pivot points used when elevating
the barrel. |
Vent
|
(Also
known as the “Touch-Hole”).
The hole which leads from the outside of the gun to
inside, right at the breech.
This is where the gun is set off.
Gunpowder is poured into the vent, and ignited,
which ignites the powder in the chamber of the gun itself. |
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