Sa vz. 23 Submachine Gun

The CZ Model 25 (properly, Sa 25 or Sa vz. 48b/samopal vz. 48b – samopal vzor 48 výsadkový, "submachine gun model year 1948 para") was perhaps the best known of a series of Czechoslovak designed submachine guns introduced in 1948. There were four generally very similar submachine guns in this series: the Sa 23, Sa 24, Sa 25, and Sa 26. The primary designer was Jaroslav Holeček (1923–1927), chief engineer of the Česká zbrojovka Strakonice arms factory.

The Sa 23 series utilize a straightforward blowback action, with no locked breech, and fire from the open bolt position. They also use a progressive trigger for selecting between semi-automatic fire and fully automatic fire. Lightly pulling on the trigger will fire a single shot. Pulling the trigger farther to the rear in a continuous motion will fire fully automatically, until the trigger is released or the magazine is empty.

The Sa 23 series were the first production-model submachine guns with a telescoping bolt, in which the forwards part of the moving bolt extends forwards past the back end of the barrel, wrapping around that barrel. This feature reduces the required length of the submachine gun significantly and allows for better balance and handling. Handling was further improved by using a single vertical handgrip housing the ammunition magazine and trigger mechanism, roughly centered along the gun's length. The gun's receiver was machined from a single circular steel tube.

The design of the Sa 23 series submachine guns is most notable in the West for having heavily inspired the slightly later Uzi submachine gun (Hogg 1979:157).

CZ Model 25
Type	Submachine gun
Place of origin	Czechoslovakia
Production history
Produced	1948–1968
Specifications
Weight	3.27 kg empty (folding stock models Sa.25, Sa.26); 3.5 kg empty (fixed wood stock models Sa.23, Sa.24)
Length	445 mm folding stock model folded (Sa.25, Sa.26); 686 mm fixed stock and unfolded folding stock
Barrel length	284 mm
Cartridge	7.62x25mm Tokarev 9x19mm Parabellum
Action	Blowback
Rate of fire	650 rpm
Feed system	24 or 40 round (9 mm Sa.23, Sa.25); 32 round (7.62 mm Sa.24, Sa.26)
Sights	Iron