Armstrong gun
An Armstrong gun was a uniquely designed type of
The Armstrong rifled breechloading guns of the 1850s-1860s
In 1854, Armstrong approached the Secretary of State for War, proposing that he construct a rifled breech-loading 3-pounder gun for trial. Later increased in bore to 5-pounder, the design performed successfully with respect to both range and accuracy. Over the next three years he developed his system of construction and adapted it to guns of heavier calibre.
Armstrong's system was adopted in 1858, initially for "special service in the field" and initially he only produced smaller
Armstrong did not consider his system suited to heavier guns but higher authorities had him develop a
Armstrong breech-loading system
Armstrong's guns used a "built-up" construction, comprising a central "A" tube (initially of wrought iron, and from 1863 of mild steel toughened in oil) holding the bore over which were shrunk several wrought iron coils which kept the central tube under compression,[1] a breech-piece, and a trunnion ring.[2] The guns' rifling was on the "polygroove" system; the bore of the gun had 38 grooves along its length with a twist of one turn per 38 calibres.
The
On top of each gunpowder
An innovative feature which is more usually associated with 20th-century guns was what Armstrong called its "grip", which was essentially a
The Armstrong breech loaders used a vertical sliding block, called a vent-piece, which had a conical copper-ringed plug on its front surface which sealed the firing chamber, to close the breech. To hold both block and plug tightly in place the guns used a hollow breech screw (hence the name "screw breech") behind the block, which the gunner rotated to tighten and seal the breech before firing.
To load and fire the gun:
- The breech screw was turned to loosen it
- The vent-piece was raised
- The shell was inserted through the hollow breech-screw and rammed home into the bore
- The powder cartridge was inserted through the breech-screw into the chamber
- A primer tube was inserted into the vent piece (only necessary for the 110-pounderdue to the size)
- The vent-piece was lowered
- The breech-screw was tightened
- A friction tubewith lanyard attached was inserted in the hole at the top of the vent-piece
- The gunner pulled the lanyard which ignited a gunpowder charge in the vent tube, the flash passed through the vent in the vent-piece, assisted by the primer if present, into the powder chamber and ignited the gunpowder charge
Armstrong guns in action
The British used Armstrong guns extensively to great effect in the
Numbers of dead Chinese lay about the guns, some most fearfully lacerated. The wall afforded very little protection to the Tartar gunners, and it was astonishing how they managed to stand so long against the destructive fire that our Armstrongs poured on them; but I observed, in more instances than one, that the unfortunate creatures had been tied to the guns by the legs.[4]
The Armstrong gun—mainly the 12-pounder—was used extensively in the
On July 4, 1868, Armstrong guns were used at the Battle of Ueno by forces supporting the Imperial government of Japan.
Armstrong guns were used against British and Indian troops during the Second Anglo-Afghan War in the Battle of Charasiab, in which Howard Hensman describes six being captured by a combined Anglo-Indian expedition under the command of Brigadier-General Baker.[5]
Return to muzzle-loading guns
In 1863 an Ordnance Select committee met to consider the merits of muzzle-loading and breech-loading guns. In 1864, even before they had concluded their investigations, the Government stopped the manufacture of Armstrong breech-loaders. When the Committee finally reported, in August 1865, they announced that:
The many-grooved system of rifling with its lead-coated projectiles and complicated breech-loading arrangements is far inferior for the general purpose of war to the muzzle-loading system and has the disadvantage of being more expensive in both original cost and ammunition. Muzzle-loading guns are far superior to breech-loaders in simplicity of construction and efficiency in this respect for active service; they can be loaded and worked with perfect ease and abundant rapidity.
Their report did admit that Armstrong's guns, while more expensive, were undoubtedly safer in that while it was not uncommon for cast iron muzzle-loaders to burst, not one Armstrong gun had ever done so. (Furthermore, gunners could clear a misfire from the breech; when the
Despite a further report which remarked on the advantages of breech-loaders, cost dominated the proceedings and the Committee finally announced that "The balance of advantages is in favour of muzzle-loading field guns", and in 1865 Britain reverted from breech-loading ordnance to muzzle-loading.[6]
Tests conducted in 1859 with the Armstrong 40-pounder, and again in 1869 with the Armstrong rifled 100-pounder had demonstrated that neither rifled cannon was capable of penetrating 4 inches of armour, even at as little as 50 yards. This was crucial because Britain, as a maritime power, relied for its security on the ability of its naval ordnance to defeat any new armour-protected warships being developed by potential enemy powers.
Armstrong developed an alternative horizontal sliding wedge version of his breechloader, for 40-pounder and 64-pounder guns, in an attempt to address the limitations of the screw breech, but the Government had already decided to return to muzzle-loading guns.
To allow rifling to be used with muzzle-loaders, Armstrong proposed in 1866 a new system whereby the shells had studs on the outside, which aligned with grooves in the barrel of the
Later Armstrong breechloaders
Armstrong returned to the manufacture of breechloaders in the 1880s, using an
See also
- Rifled breech loader
- Disappearing gun for the Armstrong Disappearing Gun.
Notes
- ^ Holley states that Daniel Treadwell first patented the concept of a central steel tube kept under compression by wrought-iron coils.. and that Armstrong's assertion that he (Armstrong) first used a wrought-iron A-tube and hence did not infringe the patent, was disingenuous, as the main point in Treadwell's patent was the tension exerted by the wrought-iron coils, which Armstrong used in exactly the same fashion. Holley, Treatise on Ordnance and Armour, 1865, pages 863–870
- ^ Armstrong Rifled Breech Loading (RBL) 6-Pounder Archived 20 February 2002 at the Wayback Machine
- ^ Treatise on Ammunition 1877, pages 166–167
- ^ Robert Swinhoe, Narrative of the North China Campaign of 1860 (London: Smith, Elder & Co, 1861) p. 105.
- ^ Howard Hensman Afghan War of 1979-80 (London, W.H. Allen & Co., 1882) p. 35.
- ^ Ruffell, WL. "The Gun - Rifled Ordnance: Whitworth". The Gun. Archived from the original on 13 February 2008. Retrieved 6 February 2008.
References
- Treatise on Ammunition. War Office, UK, 1877[permanent dead link]
- Alexander Lyman Holley, "A Treatise on Ordnance and Armor" published by D Van Nostrand, New York, 1865
Further reading
- Jack Beeching, The Chinese Opium Wars (1975), ISBN 0-15-617094-9
External links
- Friedrich Engels, ""On Rifled Cannon", articles from the New York Tribune, April, May and June, 1860, reprinted in Military Affairs 21, no. 4 (Winter 1957) ed. Morton Borden, 193–198.