Work on the vz. 23 began in 1947 as part of a large-scale project at the CZ factory to design a new submachine gun to meet the requirements of the Czech Army. Several prototypes of differing designs were developed by a team consisting of Jaroslav Holeček, František Myška, František Brejcha, Jan Kratochvíl, and Václav Zibar. One of these designs, known as the CZ 148, was favored and was developed further, with the improved prototype being designated the CZ 447. The CZ 447 was subjected to testing in both the 9×19mm and 7.62×25mm cartridges. Although the 7.62mm model encountered issues, the 9mm model was considered satisfactory and was submitted to military trials.
The CZ 447 was trialed by the Czech Army in mid-1948 against the ZK 476 from ZB. After both designs underwent modifications in August that year, it was decided that the CZ 447 would be adopted in a fixed stock model the M48a and in a folding stock model as the M48b. A full production run was ordered in late 1948.
In early 1950, the Czech Army changed their designations for the gun from the M48a to the Sa vz. 23 (the M48b became the vz. 25). Shortly thereafter, Warsaw Pact standardization was introduced which required the Czech Army to adopt the 7.62×25mm cartridge in place of 9×19mm. Thus production of the vz. 23 and vz. 25 was halted and replaced by production of the earlier 7.62×25mm model, now designated as the vz. 24. An interchangeable-caliber design that could be quickly adapted to take the 9mm cartridge was planned but ultimately not produced in large numbers on account of cost and complexity. After a production run totaling at about 100,000 units, manufacture of the vz. 23 and its variants was ended in May 1950.
The vz. 24 was adopted in June 1951, along with a folding-stock vz. 26 model. The surplus vz. 23 and vz. 25 guns were exported for international sale and saw commercial success, with orders to Cuba, Syria, Chile, and Lebanon, among other countries. The gun was popular in Rhodesia and South Africa after the introduction of local copies, including the semi-automatic Sanna 77.
The Sa vz. 23 features a pistol grip magazine well and telescoping bolt, allowing the weapon to be compact while retaining a longer barrel.
- Sa vz. 23
Variant with solid wooden stock.
- Sa vz. 24
Variant chambered in 7.62x25mm Tokarev with solid wooden stock. Can be distinguished from the Sa vz. 23 by the slight forward slant of the magazine.
- Sa vz. 25
Variant with folding stock.
- Sa vz. 26
Variant in 7.62x25mm Tokarev with folding stock.
South African semi-automatic conversion of the vz. 23.