The submachine gun was produced by the Fábrica do Braço de Prata weapon factory at Lisbon, whose initials FBP gave the name to the weapon, adopted for service as the m/948 in 1948. It utilized the large bolt and telescoping operating spring of the German MP40 submachine gun, and the collapsible wire stock of the American M3 submachine gun. Unusual for submachineguns, the m/948 was fitted with a barrel sleeve with a mount to accept the standard Portuguese Mauser bayonet.
The original version of the submachine gun (the FBP m/948) only allowed for fully automatic fire. An upgraded version (designated FBP m/963) introduced in 1961 also allowed for semi-automatic fire.
The weapon was primarily issued to officers and NCOs in the Portuguese Armed Forces and security forces, along with quantities of ex-German MP 34 submachine guns. In Portuguese service it was used in combat in Angola, Portuguese Guinea, Mozambique, Portuguese India and Portuguese Timor. It was eventually replaced in service by the 9 mm Uzi and the collapsible-stock version of the standard m/961 G3 rifle.
| FBP | |
|---|---|
| Type | Submachine Gun |
| Place of origin | Portugal |
| Service history | |
| In service | 1948-1980s |
| Used by | Portugal |
| Wars | Portuguese Colonial War |
| Production history | |
| Designer | Gonçalves Cardoso |
| Designed | 1948 |
| Manufacturer | Fábrica de Braço de Prata (FBP) |
| Produced | 1948-1955 |
| Variants | m/948, m/963 and m/976 |
| Specifications | |
| Weight | 3.77 kg (8.31 lb) |
| Length | 807 mm (31.8 in) |
| | |
| Cartridge | 9x19mm Parabellum |
| Action | Blowback |
| Rate of fire | 500 rounds/min |
| Muzzle velocity | 390 m/s (1,280 ft/s) |
| Feed system | 21, 32-round box magazine |
| Sights | Iron |
