Background on the FNAB-43
The Fabbrica Nazionale d’Armi di Brescia (FNAB), Italy designed and manufactured the FNAB-43 submachine gun between 1943-44. Approximately 7,000 manufactured FNAB-43’s were issued to German and Italian units fighting in Northern Italy. At a time when the general tendency was to build quick and cheap weapons, the FNAB-43 called for expensive engineering and time-consuming methods of precision engineering in its construction. It was a well-made and efficient weapon.
The FNAB-43 Submachine Gun.
Design Features
The action is a delayed blowback of unique design, firing from the closed bolt position. The two-piece bolt has a pivoted lever interposed between bolt head and body. On firing the bolt head moves back and begins to rotate the lever, the toe of which is abutting against a lug in the body. This pivoted lever delays the opening movement by operating at a mechanical disadvantage. This allows the bullet to leave the barrel and breech pressure to drop before the lever has completed its rotation. The movement of the lever then presses the free end against the bolt body and accelerates the bolt to the rear. The toe of the lever pulls clear of the lug and the whole bolt unit can recoil as one component in the usual way. On returning, the lever engages once more with the body lug and pivots forward. This removes an interlock that allows movement of the firing pin only when the bolt is fully forward. This unusual and complicated system allows the rate of fire to be kept down to very practical limits without using a heavy bolt or strong spring.
Other weapon features include a muzzle brake and compensator built into the barrel casing in the manner of some of the Russian weapons. It also has a hinged magazine housing that can lie beneath the barrel. The single metal bar stock can be fold so that the FNAB-43 becomes a very compact unit.
Specifications
| Model | FNAB-43 |
|---|---|
| Caliber | 9 mm |
| Barrel | 6 grooves with right-hand twist |
| Length | 31.15 inches (80.01 cm) |
| Barrel Length | 7.8 inches (19.81 cm) |
| Weight | 8 lbs 12 oz (3.97 kg) |
| Feed System | 20 or 40 round detachable box magazine |
| Rate of Fire | 400 rpm |
| System of Operation | Delayed Blowback, Selective Fire |
Source:
The Encyclopedia of Infantry Weapon of World War II
