Editing Uzi (section)

== Design ==
The Uzi uses an [[open bolt|open-bolt]], [[blowback (arms)|blowback]]-operated design, quite similar to the Jaroslav Holeček-designed Czech ZK 476 (prototype only)<ref>{{cite web|url= http://www.pmulcahy.com/submachineguns/israeli_submachineguns.htm|title= IMI Uzi|first= Paul|last= Mulcahy|access-date= 25 November 2012|archive-url= https://web.archive.org/web/20130120073355/http://pmulcahy.com/submachineguns/israeli_submachineguns.htm|archive-date= 20 January 2013|url-status=live}}</ref> and the production [[Sa vz. 23|Sa 23, Sa 24, Sa 25, and Sa 26]] series of submachine guns introduced in 1948. The open bolt design exposes the barrel's breech end, improving cooling during periods of continuous fire. However, it means that since the bolt is held to the rear when cocked, the receiver is more susceptible to contamination from sand and dirt. It uses a [[telescoping bolt]] design, in which the bolt wraps around the breech end of the barrel.<ref name="IH">{{cite book | last = Hogg | first = Ian V. | author-link = Ian V. Hogg | title = Guns and How They Work | publisher = Everest House | year = 1979 | location = New York | pages = 157–158 | isbn = 0-89696-023-4 }}</ref> This allows the barrel to be moved far back into the [[receiver (firearms)|receiver]] and the [[magazine (firearms)|magazine]] to be housed in the pistol grip, allowing for a heavier, slower-firing bolt in a shorter, better-balanced weapon.<ref name="FF"/>

The weapon is constructed primarily from stamped sheet metal, making it less expensive per unit to manufacture than an equivalent design machined from forgings. With relatively few moving parts, the Uzi is easy to strip for maintenance or repair. The magazine is housed within the pistol grip, allowing for intuitive and easy reloading in dark or difficult conditions, under the principle of "hand finds hand". The pistol grip is fitted with a [[grip safety]], making it difficult to fire accidentally. However, the protruding vertical magazine makes the gun awkward to fire when prone.<ref name="IH"/> The Uzi features a bayonet lug.<ref name="Lewis">{{cite book |title=The Gun Digest Book of Assault Weapons |last=Lewis |first=Jack |author2=Steele, David E. |author-link =Jack Lewis (screenwriter) |year=2000 |edition=5th |publisher=Krause Publications |location=Iola, Wis. |isbn=0-87341-778-X |page=222 |oclc=43521989}}</ref>
[[File:Uzi Gal.jpg|thumb|[[Uziel Gal]], the designer and inventor of the Uzi submachine gun]]

===Operation===
The non-reciprocating charging handle on the top of the receiver cover is used to retract the bolt. Variants have a ratchet safety mechanism which will catch the bolt and lock its movement if it is retracted past the magazine, but not far enough to engage the [[sear (firearm)|sear]]. When the handle is fully retracted to the rear, the bolt will cock (catch) on the sear mechanism and the handle and cover are released to spring fully forward under power of a small spring. The cover will remain forward during firing since it does not reciprocate with the bolt. The military and police versions will fire immediately upon chambering a cartridge as the Uzi is an open bolt weapon.

There are two external safety mechanisms on the Uzi. The first is the three-position selector lever located at the top of the grip and behind the trigger group. The rear position is "S", or "safe" (S = Sicher or Secure on the MP2), which locks the sear and prevents movement of the bolt.

The second external safety mechanism is the grip safety, which is located at the rear of the grip. It is meant to help prevent accidental discharge if the weapon is dropped or the user loses a firm grip on the weapon during firing.

The trigger mechanism is a conventional firearm trigger, but functions only to control the release mechanism for either the bolt (submachine gun) or firing pin holding mechanism (semi-auto) since the Uzi does not incorporate an internal cocking or hammer mechanism. While the open-bolt system is mechanically simpler than a closed-bolt design (e.g. [[Heckler & Koch MP5]]), it creates a noticeable delay between when the trigger is pulled and when the gun fires.

The magazine release button or lever is located on the lower portion of the pistol grip and is intended to be manipulated by the non-firing hand. The paddle-like button lies flush with the pistol grip in order to help prevent accidental release of the magazine during rigorous or careless handling.

When the gun is de-cocked the ejector port closes, preventing entry of dust and dirt. Though the Uzi's stamped-metal receiver is equipped with pressed reinforcement slots to accept accumulated dirt and sand, the weapon can still jam with heavy accumulations of sand in desert combat conditions when not cleaned regularly.<ref name="KD">{{cite book| last = Dockery| first =Kevin| author-link=Kevin Dockery (author)|title = Future Weapons| url = https://archive.org/details/futureweapons0000dock| url-access = limited| publisher = Berkley Caliber |location=New York | year = 2007| pages = [https://archive.org/details/futureweapons0000dock/page/227 227]–229| isbn = 978-0-425-21750-4 }}</ref> The magazine must be removed prior to de-cocking the weapon.

=== Stocks ===
[[File:1952 General von Horn IMI Uzi 001 (cropped).jpg|thumb|Uzi with a detachable wooden stock]]
[[File:UZI Submachine Gun (7414624230).jpg|thumb|Uzi with a folding stock]]

There are different stocks available for the Uzi proper.<ref>{{cite book|last1=Gaboury|first1=David|title=The UZI Submachine Gun Examined|date=3 July 2017|publisher=Andrew Mowbray Publishing, Inc.|isbn=978-1931464765|page=234}}</ref> There is a wooden stock with a metal buttplate that comes in three similar variations that were used by the IDF. The first version had a flat butt and straight [[Stock (firearms)#Comb|comb]] and had hollows for a cleaning rod and gun oil bottle. The second had an angled butt and a straight comb and no hollows. The third had an angled butt and curved comb and no hollows; a polymer version is currently available from IMI. The wooden stocks originally had a quick-release base but the ones sold in the United States often had a permanent base for legal reasons, as detachable stocks on pistols or other short-barreled weapons upgrade the weapon to [[National Firearms Act|NFA]] status.<ref>{{cite web |title= FAQ |url=https://www.uzitalk.com/reference/pages/FAQ.htm#Barrel%20and%20stock |website=UZI Talk }}</ref><ref>{{cite web |title=If a person has a pistol and an attachable shoulder stock, does this constitute possession of an NFA firearm?  |url=https://www.atf.gov/firearms/qa/if-person-has-pistol-and-attachable-shoulder-stock-does-constitute-possession-nfa |website=Bureau of Alcohol, Tobacco, Firearms and Explosives |date=April 13, 2020 }}</ref>

Choate made an aftermarket polymer stock with a rubber butt-pad that had a flat butt, a straight comb, and a permanent base.

In 1956,<ref>{{cite book|last1=Gaboury|first1=David|title=The UZI Submachine Gun Examined|date=3 July 2017|publisher=Andrew Mowbray Publishing, Inc.|isbn=978-1931464765|page=40}}</ref> IMI developed a downward-folding twin-strut metal stock with two swivelling sections that tuck under the rear of the receiver. The Mini Uzi has a forward-folding single-strut metal stock that is actually an inch longer than the Uzi's. Its buttplate can be used as a foregrip when stowed. The Micro Uzi has a similar model.

=== Magazines ===
The original box magazines for the 9mm Uzi had a 25-round capacity. Experimental 40- and 50-round extended magazines were tried but were found to be unreliable. A 32-round extended magazine was then tried and was later accepted as standard. The Mini Uzi and Micro Uzi use a shorter 20-round magazine. Available extended magazines include 40-, and 50-round magazines. Other high-capacity aftermarket magazines exist such as the Vector Arms 70-round and Beta Company ([[Beta C-Mag]]) 100-round [[Drum magazine|drums]].

The .45 ACP Uzi used a 16- or 22-round magazine, while the .45 ACP Micro Uzi and Mini Uzi used a 12-round magazine. A conversion kit by Vector Arms allowed the .45-caliber Uzi to use the same 30-round magazines as the [[M3 submachine gun|M3 "Grease Gun"]].{{r|mcnab2011|p=20–25}}

=== Caliber conversions ===
The Uzi was available with caliber conversion kits in .22 LR or [[.41 AE]]. The operator just has to change the barrel, bolt and magazine. The .22 LR had 20-round magazines; the original IMI kit used a barrel insert while the aftermarket Action Arms kit used a full replacement barrel. The .41 AE also had a 20-round magazine; since it has the same bolt face as the 9×19mm Parabellum, only the barrel and magazine needed to be changed.{{r|mcnab2011|p=20–25}}

IMI also manufactured a .45ACP conversion kit both in full auto/open bolt with a 10.2" barrel for the 9mm SMG and a semi only/closed bolt with a 16" barrel for the carbine version. Magazine capacity is limited, with 2 sizes of 16 and 10 rds each.