Sa vz. 58

Infobox Weapon
name=Sa vz. 58


caption=Sa vz. 58 P (composite stock, new sling).
origin=flag|Czechoslovakia
type=Assault rifle
is_ranged=yes
service=1959–present
used_by=See "Users"
wars=
designer=Jiří Čermák
design_date=1956–1958
manufacturer=Česká Zbrojovka
production_date=1959–1984
number=Approx. 920,000
variants=See "Variants"
weight=kg to lb|2.91|sp=us|abbr=on|precision=2|wiki=yes
length=mm to in|845|abbr=on|precision=1|wiki=yes (vz. 58 P) convert|845|mm|abbr=on|1 stock extended / convert|636|mm|abbr=on|1 stock folded (vz. 58 V) convert|1000|mm|abbr=on|1 with bayonet fixed
part_length=convert|390|mm|abbr=on|1
width=convert|57|mm|abbr=on|1 stock extended convert|72|mm|abbr=on|1 stock folded
height=convert|255|mm|abbr=on|1
cartridge=7.62x39mm M43
action=Gas-operated, falling breechblock
rate=800 rounds/min
velocity=convert|705|m/s|0|lk=on|sp=us|abbr=on Muzzle energy: 1988 J
range=100–800 m sight adjustments
max_range=2,800 m
feed=Staggered 30-round detachable box magazine, weight convert|0.19|kg|abbr=on unloaded
sights=Open-type iron sights with sliding rear tangent and shrouded front post convert|353|mm|abbr=on|1 sight radius

The Sa vz. 58 is a 7.62 mm assault rifle designed and manufactured in Czechoslovakia and accepted into service as the "7,62 mm samopal vzor 58" ("7.62 mm submachine gun model 1958"), replacing the 7.62 mm vz. 52 self-loading rifle and the 7.62 mm Sa vz. 24 and Sa vz. 26 submachine guns. The vz. 58 bears a superficial resemblance to the Soviet AK-47 but the two weapons are not related.

Development

Development of the weapon began in 1956; leading the project was chief engineer Jiří Čermák assigned to the Konstrukta Brno facility in the city of Brno. The prototype, known as the "Koště" ("broom"), was designed to chamber the intermediate Soviet 7.62x39mm M43 cartridge, rather than the Czech 7.62x45mm vz. 52 round, used in both the earlier vz. 52 rifle and the vz. 52 light machine gun. The assault rifle entered service in 1958 and over a period of 25 years (until 1984), over 920,000 weapons had been produced, fielded by the armed forces of the Czech and Slovak Republics, Cuba and several other Asian and African nations.

The vz. 58 was produced in three main variants: the standard vz. 58 P ("Pěchotní" – "infantry") model – with a fixed buttstock made of a synthetic material (wood impregnated plastic, older versions used a wooden stock), the vz. 58 V ("Výsadkový" – "airborne") – featuring a side-folding metal shoulder stock, folded to the right side, and the vz. 58 Pi ("Pěchotní s infračerveným zaměřovačem" - "infantry with infrared sight"), which is similar to the vz. 58 P but includes a long receiver-mounted dovetail bracket (installed on the left side of the receiver) used to attach an NSP-2 night sight; it also has a detachable folding bipod and an enlarged conical flash suppressor.

Design details

The vz. 58 is a selective fire gas-operated weapon that bleeds expanding combustion gases from the ignited cartridge through a port, drilled in the barrel convert|215|mm|abbr=on|1 from the breech face, opening into a hollow cylinder located above the barrel that contains a short-stroke piston. The vz. 58 does not have a gas regulator and the full force of the gas pressure is exerted on the piston head, propelling it backwards in a single impulsive blow. The piston is driven back only convert|19|mm|abbr=on|1 when a shoulder on the piston rod butts against the seating and no further movement is possible. There is a light return spring held between the piston shoulder and the seating which returns the piston to its forward position. The gas cylinder is vented after the piston has traveled back convert|16|mm|abbr=on|1 and the remaining gases are exhausted into the atmosphere on the underside of the cylinder. The entire piston rod is chromium-plated to prevent fouling.

The locking system features a falling breech lock hinged from the breech block and breech block carrier that contains two locking lugs which descend into and engage locking shoulders in the receiver’s internal guide rails. The weapon is unlocked by the short tappet-like stroke of the piston rod as it strikes the breech block carrier and drives it rearwards. After convert|22|mm|abbr=on|1 of unrestricted travel, an inclined surface on the carrier moves under the locking piece and lifts it up and out of engagement with the locking shoulders in the steel body. The breech locking piece swings and this movement provides the leverage required for primary extraction. The breech block is then carried rearwards extracting the empty cartridge casing from the chamber. A fixed ejector passes through a groove cut in the underside of the bolt and the case is flung upwards clear of the gun. The spring-loaded extractor and firing pin are both housed inside the breech lock, while the fixed ejector is located at the base of the receiver.

The weapon does not have a conventional rotating hammer but is striker-fired and the striker is a steel bar hollowed from one end almost throughout its entire length to accommodate its own operating spring. At the open end of the striker, a plate is welded and there is a groove cut ineach side of this to slide on the receiver guide rails. This hammer-striker enters the hollow bolt and drives a fully floating firing pin forward with each shot. The rifle uses a trigger mechanism with a lever-type fire mode selector, which is also a manual safety against accidental firing. When the selector lever is placed in its rear position ("1" – single fire) the sear is disabled and the left striker catch is rotated by the disconnector, which is depressed by the bolt carrier after every shot and is therefore disconnected from the striker catch. The forward setting of the selector lever ("30" – automatic fire) disables the disconnector, and the left striker catch meshes with the sear mechanism. The center ("safe") setting with the selector lever pointing vertically downwards, mechanically lowers the trigger bar and the disconnector so there is no connection between the trigger and the semi-automatic sear which holds the hammer. The rifle also has an internal safety, which prevents the weapon from discharging prematurely. The right striker-hammer catch disables the striker-hammer, and it can only be released by pulling the charging handle back and cocking the weapon.

The weapon is fed from a detachable box magazine with a 30-round cartridge capacity and made from a lightweight alloy. When the last round from the magazine is fired, the bolt will remain locked open on the bolt catch, activated by the magazine’s follower. The magazine release tab is located at the base of the receiver, behind the magazine well. The bolt carrier has a built-in guide rail used for reloading from 10-round stripper clips (from the SKS rifle). Despite their similarity, vz. 58 magazines are not interchangeable with those of the AK-47 and its derivatives.

The rifle’s iron sights consist of a fully adjustable front post and a tangent rear sight with a sliding notch with range settings from 100 to 800 m, graduated every 100 m. Besides this, the left sight of the rear sight leaf is marked with the letter "U" ("univerzální"), for snap shooting, firing at moving targets and night combat at ranges up to 300 m. The front sight base also serves as a mounting platform for the vz. 58 edged bayonet.

Additional equipment supplied with the rifle includes: 4 spare magazines, a magazine pouch, vz. 58 bayonet and scabbard, cleaning brush, muzzle cap, oil bottle, unified sling, front sight adjustment tool and a threaded blank-firing adaptor.

A successor to the vz. 58 was proposed in the 1990s; the 5.56x45mm NATO ČZ 2000 assault rifle has been suggested as a possible replacement but due to a general lack of defense funds within the Czech Republic, the program was postponed.

Variants

*Vz. 58 P: Standard fixed stock.
*Vzor 58 V: Metal folding stock version for vehicle crew and airborne units.
*Vzor 58 Pi: Has a mounting for an infrared night vision NSP-2 sight, fixed stock, cone flash hider and folding bipod.
*"Automatická puška" ("automatic rifle") AP-Z 67: Experimental 7.62x51mm NATO caliber version developed in 1966.
*"Útočná puška" ("assault rifle") ÚP-Z 70: Experimental 5.56x45mm NATO version developed in 1970.
*"Experimentální zbraň" ("experimental weapon") EZ-B: Experimental bullpup prototype developed in 1976.
*"Ruční kulomet" ("light machine gun") codename KLEČ ("dwarf pine"): Experimental variant with a 590 mm barrel (similar to RPK), developed in 1976.
*"Lehká odstřelovačská puška" ("light sniper rifle") vz. 58/97: Experimental marksman rifle developed by VTÚVM Slavičín.
*"Samopal" ("submachine gun") vz. 58/98 "Bulldog": 9x19mm Parabellum variant developed by VTÚVM Slavičín.
*CZH 2003 Sport: Semi-automatic only variant for civilian consumption. Available with either a standard 390 mm or shortened 295 mm barrel.
*CZ 858 Tactical (in Canada VZ-58S): A semi-automatic variant designed for the civilian market in Canada. Available with standard or extended (482 mm) barrel lengths. External components have a new varnish coat (identical to the coating used on original military rifles).
*FSN01: Civilian semi-automatic variant. Available in standard or shortened (279 mm) barrel lengths, outer parts are blued.

Users

*flag|Angola
*flag|Cuba
*flag|Czech Republic: Standard service rifle. [ [http://www.army.cz/scripts/detail.php?id=5080 Czech army vz. 58 page.] ]
*flag|Czechoslovakia
*flag|Cyprus
*flag|Dominican Republic
*flag|Ethiopia
*flag|India
*flag|Indonesia
*flag|Iraq
*flag|Lebanon [ [http://www.lebaneseforces.com/wassaultrif.asp Lebanese Forces Weapons Page.] Retrieved on July 28, 2007.]
*flag|Libya
*flag|Slovakia
*flag|Sudan

Notes

ee also

*AKM

External links

* [http://www.czub.cz/index.php?p=32&idp=9&ids=36&idz=224&lang=en Česká Zbrojovka - official site]
* [http://www.czub.cz/navody/cz58_en.pdf Instruction manual]
* [http://world.guns.ru/assault/as33-e.htm Modern Firearms]