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{{about|the projectile sabot|other meanings of "sabot"|sabot (disambiguation)}}
[[File:Paixhans Shell and Sabot.jpg|thumb|[[Shell (projectile)|Shell]] with sabot in a 1824 [[Paixhans gun]]]]
[[File:Delvigne system.jpg|thumb|Lead bullet being supported by a wooden sabot in a [[Henri-Gustave Delvigne|Delvigne gun]]]]
[[File:Sabot separating.gif|thumb|An [[Kinetic energy penetrator|APFSDS]] separating from its spindle sabot]]
[[File:Obus 501556 fh000022.jpg|thumb|Anti-tank round with its sabot]]
A '''sabot''' {{IPAc-en|'|s|{|b|@U}} is a device used in a [[firearm]] or [[cannon]] to fire a [[projectile]], such as a [[bullet]], that is smaller than the [[caliber|bore]] diameter, or which must be held in a precise position.

==Design==
Since a strong seal is needed to trap [[propellant]] gases behind the projectile, and keep the projectile centered in the [[barrel (firearms)|barrel]], something is needed to fill the undesirable but necessary gap between projectile and barrel, a space referred to as the [[windage]], and this is the role of the sabot.  Firing a small size projectile wrapped in a sabot raises the muzzle velocity of the projectile.  Made of some lightweight material (usually plastic in smallbore guns, and aluminium - and, in earlier times, wood or [[papier-mâché]] - in cannons), the sabot usually consists of several pieces held in place by the cartridge or a loose connection.  When the projectile is fired, the sabot blocks the gas, and carries the projectile down the barrel.  When the sabot reaches the end of the barrel, the shock of hitting still air pulls the parts of the sabot away from the projectile, allowing the projectile to continue in flight.

Sabots are used to fire the [[flechettes]] that form anti-armour [[kinetic energy penetrator]]s. A sabot is also used to fire anti-personnel flechette rounds. This round consists of the outer cup (sabot) which holds numerous subcaliber darts. The sabot cup holds the individual flechettes together tightly until the sabot case separates after leaving the barrel. For reasons why a smaller diameter projectile can be desirable, see [[external ballistics]] and [[terminal ballistics]].

Sabot-type shotgun slugs were marketed in the U.S. starting in about 1985.  When used with a [[rifled]] [[slug barrel]], they offer vastly improved accuracy compared to traditional shotgun slugs.  They are now legal for hunting in most states.

==Types of sabots==
[[File:Sabot types.svg|thumb|left|Sabot types:<br>
1. Cup type sabot<br>
2. Expanding cup sabot<br>
3. Base sabot<br>
4. Spindle sabot<br>
5. Ring sabot]]
[[File:Shotgun-shot-sequence-1g.jpg|right|thumb| Series of individual 1/1,000,000 second exposures showing shotgun firing shot and expanding cup sabot separation.]]

===Cup sabot===
A cup sabot merely supports the base and rear end of a projectile.  When the sabot and projectile exit the muzzle of the gun, air pressure on the sabot forces the sabot to release the projectile.

<!-- I'm confused about where the rotation comes from - the muzzle-loaded gun referred to isn't rifled, is it? Or is the rotation a tumbling rather than an axial spin? ~~~~-->===Expanding cup sabot===
Used typically in small arms (most commonly [[muzzleloader]]s), an expanding cup sabot has a one piece sabot surrounding the base and sides of a projectile.  Upon firing, when the sabot and projectile leave the muzzle of the gun, inertia from the rotation of the projectile and sabot opens up the segments surrounding the projectile, releasing it.

===Base sabot===
A base sabot has a one piece base which supports the bottom of the projectile, and separate pieces that surround the sides of the projectile and center it.

The base sabot has better and cleaner sabot/projectile separation than cup or expanding cup sabots, but is more expensive since more pieces are involved.

===Spindle sabot===
A spindle sabot uses a set (usually two) of matched rings which have a center section in contact with a long projectile, front sections which center that projectile in the barrel, and a rear section which both centers the projectile and seals propellant gases.

Spindle sabots are the standard western type of armor-piercing ammunition.  Two- and three-piece spindle-type sabots are shown in the illustrations at the right of this paragraph.

[[Shotgun slug]]s often use a cast plastic sabot similar to the spindle sabot.  Shotgun sabots in general extend the full length of the projectile and are designed to be used in [[rifled]] barrels.

===Ring sabot===
[[File:125mm Bm15 APFSDS.JPG|thumb|right|Soviet BM-15 Armor piercing round with ring sabot]]

A ring sabot uses the rear fins on a long projectile to help center the projectile, and the multi-piece sabot forms only a single thin ring around the projectile near the front, sealing gases from escaping past it and centering the front of the projectile.

Because the rear fins have to have the same diameter as the gun bore, they typically are larger than is optimum for flight performance.

Several Soviet and current Russian design armor-piercing sabot projectiles use ring sabots.

==See also==
*[[Shell (projectile)]]
*[[Armour-piercing discarding sabot]]
*[[Gas check]]
*[[Obturate]]
*[[Saboted Light Armor Penetrator (SLAP)]]

==External links==
{{Wiktionary|sabot}}
{{Commons}}
*[http://people.rit.edu/andpph/exhibit-shotgun-blast.html Shotgun sabot separation photography]
*[http://www.army-technology.com/contractors/ammunition/cime_bocuze/cime_bocuze1.html PLANSEE Tungsten Ammunition Components at Army Technology.com, accessed December 30, 2012]

{{Wikipedia|Sabot}}

[[Category:Artillery ammunition]]
[[Category:Anti-tank rounds]]
[[Category:Ballistics]]
[[Category:Firearm terminology]]