L74
| Bofors L74 | |
|---|---|
 Schematic illustration of the Bofors L74 gun installation inside the Strv 103 hull. | |
| Type | Tank gun |
| Place of origin | Sweden |
| Service history | |
| In service | 1967-1997 |
| Used by | Sweden |
| Production history | |
| Designer | Bofors |
| Manufacturer | Bofors |
| Specifications | |
| Mass | 1713 kg |
| Length | 6.51 metres (21.4 ft) |
| Shell | 105×617mmR |
| Caliber | 105 millimetres (0.344 ft) |
| Barrels | 1 |
| Breech | Vertical sliding wedge |
| Recoil | 240 mm (normal) 250 mm (maximum) |
| Sights | Jungner OPS-1 binocular periscopic sight |
The Bofors L74 is a Swedish 105 mm rifled tank gun developed specifically for the Stridsvagn 103, a turretless main battle tank. The gun was designed to be integrated into the vehicle's fixed superstructure in conjunction with an automatic loading system.
History
The development of the Strv 103's main armament was part of the Swedish Stridsvagn S programme, which sought to develop a turretless main battle tank with a fixed gun and an automatic loading system. Bofors was responsible for the development of the vehicle's main armament and its associated loading mechanism.
The L74 was designed around a 105 mm calibre and featured a longer barrel than conventional 105 mm tank guns of the period. Its integration into the Strv 103 required a dedicated breech mechanism, mounted in an upside-down configuration to accommodate the automatic loading system, as well as associated loading and extraction mechanisms.
Additional specifications
| Characteristic | Specification |
|---|---|
| Calibre | 105 mm |
| Ammunition | 105×617mmR NATO |
| Barrel length | 6,510 mm |
| Barrel length (calibres) | L/62 |
| Number of rifling grooves | 28 |
| Rifling depth | 1.15 mm |
| Rifling width | 7.9 mm |
| Rifling twist | 1 turn in 18 calibres |
| Breech mechanism | Vertical sliding wedge |
| Normal recoil length | 240 mm |
| Maximum recoil length | 250 mm |
| Minimum recoil length for cartridge case ejection | 110 mm |
| Barrel weight | 900 kg |
| Breech ring weight | 41 kg |
| Rear assembly weight (excluding mechanism) | 512 kg |
| Breech block weight | 50 kg |
References
- ↑ Ogorkiewicz, Richard M. (1991). Technology of Tanks. United Kingdom: Jane's Information Group Limited. pp. 424. ISBN 0-7106-0595-1.
- ↑ Ogorkiewicz, R. M. (1971). S-Tank. AFV Weapons Profile. Windsor: Profile Publications Ltd. p. 24.
- ↑ 103 B Vapen – DKF, Chapter 15: 105 mm L74 (Report) (in Swedish). Försvarets materielverk. 10 June 1970.
Sources
- Strv 103: Beskrivning del 2 – Data, konstruktion och funktion: Vapen (in Swedish). Bofors. 10 June 1970. pp. 5–20, 21–44.