The Broadwell ring is a small
obturating ring
{{Other uses, Obturator (disambiguation){{!Obturator
An obturating ring is a ring of relatively soft material designed to obturate under pressure to form a seal. Obturating rings are often found in artillery and other ballistics applications, and ...
used in 1860s and 1870s
rifled breech loader
A rifled breech loader (RBL) is an artillery piece which, unlike the smoothbore cannon and rifled muzzle loader (RML) which preceded it, has rifling in the barrel and is loaded from the breech at the rear of the gun.
The spin imparted by the gun ...
s in Continental Europe to ensure
obturation
In the field of firearms and airguns, obturation denotes necessary barrel blockage or fit by a deformed soft projectile (obturation in general is closing up an opening). A bullet or pellet, made of soft material and often with a concave base, wi ...
(usually in sliding wedge breechlocks). American engineer
Lewis Wells Broadwell
Lewis may refer to:
Names
* Lewis (given name), including a list of people with the given name
* Lewis (surname), including a list of people with the surname
Music
* Lewis (musician), Canadian singer
* "Lewis (Mistreated)", a song by Radiohead ...
who worked as sales agent for the
Gatling Gun
The Gatling gun is a rapid-firing multiple-barrel firearm invented in 1861 by Richard Jordan Gatling. It is an early machine gun and a forerunner of the modern electric motor-driven rotary cannon.
The Gatling gun's operation centered on a cyc ...
Company in Europe replaced a papier-mache obturating cup behind the bagged charge in early bag-loaded RBLs with a metallic gas ring and patented his invention in 1861, later perfecting it in 1864 and 1866; most countries paid royalties to Broadwell for the design, but in Germany the Krupp company stole it and used it without paying.
The ring sits in a recess at the rear end of the
bore
Bore or Bores often refer to:
*Boredom
* Drill
Relating to holes
* Boring (manufacturing), a machining process that enlarges a hole
** Bore (engine), the diameter of a cylinder in a piston engine or a steam locomotive
** Bore (wind instruments), ...
, and abuts against a flat plate. When the gun is fired, the rapidly expanding gases produced by the combustion of gunpowder force the Broadwell Ring against the plate, sealing the end of the bore against escape and directing the full force of the explosion toward propelling the
bullet
A bullet is a kinetic projectile, a component of firearm ammunition that is shot from a gun barrel. Bullets are made of a variety of materials, such as copper, lead, steel, polymer, rubber and even wax. Bullets are made in various shapes and co ...
.
The Broadwell ring is readily removed and replaced for maintenance purposes.
In late 1870s-1880s it was superseded either by a plastic obturating ring from asbestos and grease invented by
Charles Ragon de Bange
Charles Ragon de Bange (17 October 1833 – 9 July 1914) was a French artillery officer and Polytechnician. He invented the first effective obturator system for breech-loading artillery, which remains in use. He also designed a system of field g ...
or drawn brass cases, when like all other metallic obturators it became more liable to damage after the introduction of smokeless powder.
[ s:Page:EB1911_-_Volume_20.djvu/233] However, two British 120 mm tank guns (
L11 and
L30) still use sliding wedge breechblocks with obturating rings in order to fire their bagged ammo.
References
External links
MODERN ORDNANCE, A paper read Feb. 8, 1882, before the Society of Arts, London, By COLONEL MAITLAN
Artillery components
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