Editing Shell (projectile) (section)

==Modern shell==
The mid–19th century saw a revolution in artillery, with the introduction of the first practical [[Rifled breech loader|rifled breech loading]] weapons. The new methods resulted in the reshaping of the spherical shell into its modern recognizable cylindro-conoidal form. This shape greatly improved the in-flight stability of the projectile and meant that the primitive time fuzes could be replaced with the percussion fuze situated in the nose of the shell. The new shape also meant that further, armour-piercing designs could be used.

During the 20th century, shells became increasingly streamlined. In World War I, ogives were typically two circular radius head (crh) – the curve was a segment of a circle having a radius of twice the shell caliber. After that war, ogive shapes became more complex and elongated. From the 1960s, higher quality steels were introduced by some countries for their HE shells, this enabled thinner shell walls with less weight of metal and hence a greater weight of explosive. Ogives were further elongated to improve their ballistic performance.

===Rifled breech loaders===
{{main|Rifled breech loader}}
[[File:Sagahan Armstrong gun used at the Battle of Ueno against the Shogitai 1868.jpg|thumb|The [[Armstrong gun]] was a pivotal development for modern artillery as the first practical [[rifled breech loader]]. Pictured, deployed by [[Japan]] during the [[Boshin war]] (1868–69).]]
Advances in metallurgy in the industrial era allowed for the construction of [[rifled breech loader|rifled breech-loading guns]] that could fire at a much greater [[muzzle velocity]]. After the British artillery was shown up in the [[Crimean War]] as having barely changed since the [[Napoleonic Wars]], the industrialist [[William Armstrong, 1st Baron Armstrong|William Armstrong]] was awarded a contract by the government to design a new piece of artillery. Production started in 1855 at the [[Elswick Ordnance Company]] and the [[Royal Arsenal]] at [[Woolwich]].<ref>{{cite journal |last=Bastable |first=Marshall J. |year=1992 |title=From Breechloaders to Monster Guns: Sir William Armstrong and the Invention of Modern Artillery, 1854–1880 |journal=Technology and Culture |doi=10.2307/3105857 |volume=33 |issue=2 |pages=213–247 |jstor=3105857|s2cid=112105821 }}</ref><ref>{{Cite web|url=https://www.gracesguide.co.uk/William_Armstrong|title=William George Armstrong - Graces Guide|website=www.gracesguide.co.uk}}</ref>

The piece was [[rifling|rifled]], which allowed for a much more accurate and powerful action. Although rifling had been tried on small arms since the 15th century, the necessary machinery to accurately rifle artillery only became available in the mid-19th century. [[Martin von Wahrendorff]] and [[Joseph Whitworth]] independently produced rifled cannons in the 1840s, but it was Armstrong's gun that was first to see widespread use during the Crimean War.<ref>{{cite web |url=http://www.au.af.mil/au/awc/awcgate/gabrmetz/gabr001b.htm |archive-url=https://web.archive.org/web/19990819063641/http://www.au.af.mil/au/awc/awcgate/gabrmetz/gabr001b.htm |url-status=dead |archive-date=19 August 1999 |title=The Emergence of Modern War}}</ref> The [[cast iron]] shell of the Armstrong gun was similar in shape to a [[Minié ball]] and had a thin lead coating which made it fractionally larger than the gun's bore and which engaged with the gun's [[rifling]] grooves to impart spin to the shell. This spin, together with the elimination of [[British ordnance terms#Windage|windage]] as a result of the tight fit, enabled the gun to achieve greater range and accuracy than existing smooth-bore muzzle-loaders with a smaller powder charge.

The gun was also a breech-loader. Although attempts at breech-loading mechanisms had been made since medieval times, the essential engineering problem was that the mechanism could not withstand the explosive charge. It was only with the advances in [[metallurgy]] and [[precision engineering]] capabilities during the [[Industrial Revolution]] that Armstrong was able to construct a viable solution. Another innovative feature was what Armstrong called its "grip", which was essentially a [[squeeze bore]]; the 6 inches of the bore at the muzzle end was of slightly smaller diameter, which centered the shell before it left the barrel and at the same time slightly [[swage]]d down its lead coating, reducing its diameter and slightly improving its ballistic qualities.

Rifled guns were also developed elsewhere – by Major Giovanni Cavalli and Baron [[Martin von Wahrendorff]] in Sweden, [[Krupp]] in Germany and the [[Wiard rifle|Wiard gun]] in the United States.<ref>Hogg, pp. 80–83.</ref> However, rifled barrels required some means of engaging the shell with the rifling. Lead coated shells were used with the [[Armstrong gun]], but were not satisfactory so studded projectiles were adopted. However, these did not seal the gap between shell and barrel. Wads at the shell base were also tried without success.

In 1878, the British adopted a copper "[[Gas check|gas-check]]" at the base of their studded projectiles and in 1879 tried a rotating gas check to replace the studs, leading to the 1881 automatic gas-check. This was soon followed by the Vavaseur copper [[driving band]] as part of the projectile. The driving band rotated the projectile, centered it in the bore and prevented gas escaping forwards. A driving band has to be soft but tough enough to prevent stripping by rotational and engraving stresses. [[Copper]] is generally most suitable but [[cupronickel]] or [[gilding metal]] were also used.<ref name="Hogg pg 165 - 166">Hogg, pp. 165–166.</ref>

===Percussion fuze===
{{main|Artillery fuze}}
[[File:No 1 DA Percussion Fuze Mk III Diagram.jpg|thumb|Early British "direct action" nose impact fuze of 1900 with no safety or arming mechanism, relying on heavy direct physical impact to detonate]]
Although an early percussion fuze appeared in 1650 that used a flint to create sparks to ignite the powder, the shell had to fall in a particular way for this to work and this did not work with spherical projectiles. An additional problem was finding a suitably stable "percussion powder". Progress was not possible until the discovery of [[Mercury(II) fulminate|mercury fulminate]] in 1800, leading to priming mixtures for small arms patented by the Rev [[Alexander John Forsyth|Alexander Forsyth]], and the copper percussion cap in 1818.

The percussion fuze was adopted by Britain in 1842. Many designs were jointly examined by the army and navy, but were unsatisfactory, probably because of the safety and arming features. However, in 1846 the design by Quartermaster Freeburn of the Royal Artillery was adopted by the army. It was a wooden fuze about 6&nbsp;inches long and used shear wire to hold blocks between the fuze magazine and a burning match. The match was ignited by propellant flash and the shear wire broke on impact. A British naval percussion fuze made of metal did not appear until 1861.<ref>Hogg, pp. 203–203.</ref>

====Types of fuzes====
{{div col}}
* [[Artillery fuze#Percussion fuzes|Percussion fuzes]]
** [[Artillery fuze#Direct action fuzes|Direct action fuzes]]
** [[Artillery fuze#Graze fuzes|Graze fuzes]]
** [[Artillery fuze#Delay fuzes|Delay fuzes]]
** [[Artillery fuze#Base fuzes|Base fuzes]]
* [[Artillery fuze#Airburst fuzes|Airburst fuzes]]
** [[Artillery fuze#Time fuzes|Time fuzes]]
** [[Artillery fuze#Proximity fuzes|Proximity fuzes]]
** [[Artillery fuze#Distance measuring fuzes|Distance measuring fuzes]]
** [[Artillery fuze#Electronic time fuzes|Electronic time fuzes]]
{{div col end}}

===Smokeless powders===
{{main|Smokeless powder}}
[[File:Poudre B.JPG|thumb|left|[[Poudre B]] was the first practical [[smokeless powder]]]]

[[Gunpowder]] was used as the only form of explosive up until the end of the 19th century. Guns using black powder [[ammunition]] would have their view obscured by a huge cloud of smoke and concealed shooters were given away by a cloud of smoke over the firing position. [[Guncotton]], a nitrocellulose-based material, was discovered by [[Swiss people|Swiss]] chemist [[Christian Friedrich Schönbein]] in 1846. He promoted its use as a blasting explosive<ref name="Handloading28">Davis, William C., Jr. ''Handloading''. National Rifle Association of America (1981). p.&nbsp;28.</ref> and sold manufacturing rights to the [[Austrian Empire]]. Guncotton was more powerful than gunpowder, but at the same time was somewhat more unstable. John Taylor obtained an English patent for guncotton; and John Hall & Sons began [[Faversham explosives industry|manufacture in Faversham]]. British interest waned after an explosion destroyed the Faversham factory in 1847. Austrian Baron [[Wilhelm Lenk von Wolfsberg]] built two guncotton plants producing artillery propellant, but it was dangerous under field conditions, and guns that could fire thousands of rounds using gunpowder would reach their service life after only a few hundred shots with the more powerful guncotton.

Small arms could not withstand the pressures generated by guncotton. After one of the Austrian factories blew up in 1862, [[Stowmarket Guncotton Company|Thomas Prentice & Company]] began manufacturing guncotton in [[Stowmarket]] in 1863; and British [[War Office]] chemist Sir [[Frederick Abel]] began thorough research at [[Waltham Abbey Royal Gunpowder Mills]] leading to a manufacturing process that eliminated the impurities in nitrocellulose making it safer to produce and a stable product safer to handle. Abel patented this process in 1865, when the second Austrian guncotton factory exploded. After the Stowmarket factory exploded in 1871, Waltham Abbey began production of guncotton for torpedo and mine warheads.<ref name="sharpe141">Sharpe, Philip B. ''Complete Guide to Handloading''. 3rd edition (1953). Funk & Wagnalls. pp.&nbsp;141–144.</ref>

[[File:Heike Kamerlingh Onnes - 33 - James Dewar in the Royal Institution in London, around 1900.png|thumb|upright|Sir [[James Dewar]] developed the [[cordite]] explosive in 1889]]
In 1884, [[Paul Vieille]] invented a smokeless powder called [[Poudre&nbsp;B]] (short for ''poudre blanche''—white powder, as distinguished from [[gunpowder|black powder]])<ref name="Chemistry289">Davis, Tenney L. ''The Chemistry of Powder & Explosives'' (1943), pages&nbsp;289–292.</ref> made from 68.2% insoluble [[nitrocellulose]], 29.8% soluble nitrocellusose gelatinized with [[diethyl ether|ether]] and 2% paraffin. This was adopted for the Lebel rifle.<ref name="Artillery139">Hogg, Oliver F. G. ''Artillery: Its Origin, Heyday and Decline'' (1969), p.&nbsp;139.</ref> Vieille's powder revolutionized the effectiveness of small guns, because it gave off almost no smoke and was three times more powerful than black powder. Higher [[muzzle velocity]] meant a flatter [[trajectory]] and less wind drift and bullet drop, making 1000 meter shots practicable. Other European countries swiftly followed and started using their own versions of Poudre&nbsp;B, the first being [[Germany]] and [[Austria]] which introduced new weapons in 1888. Subsequently, Poudre&nbsp;B was modified several times with various compounds being added and removed. [[Krupp]] began adding [[diphenylamine]] as a stabilizer in 1888.<ref name="sharpe141"/>

Britain conducted trials on all the various types of propellant brought to their attention, but were dissatisfied with them all and sought something superior to all existing types. In 1889, Sir [[Frederick Abel]], [[James Dewar]] and W.&nbsp;Kellner patented (No.&nbsp;5614 and No.&nbsp;11,664 in the names of Abel and Dewar) a new formulation that was manufactured at the Royal Gunpowder Factory at Waltham Abbey. It entered British service in 1891 as [[Cordite]] Mark&nbsp;1. Its main composition was 58% nitro-glycerine, 37% guncotton and 3% mineral jelly. A modified version, Cordite&nbsp;MD, entered service in 1901, this increased guncotton to 65% and reduced nitro-glycerine to 30%, this change reduced the combustion temperature and hence erosion and barrel wear. Cordite could be made to burn more slowly which reduced maximum pressure in the chamber (hence lighter breeches, etc.), but longer high pressure – significant improvements over gunpowder. Cordite could be made in any desired shape or size.<ref name="Artillery141">Hogg, Oliver F. G. ''Artillery: Its Origin, Heyday and Decline'' (1969), p.&nbsp;141.</ref> The creation of cordite led to a lengthy court battle between Nobel, Maxim, and another inventor over alleged British [[patent]] infringement.