| 55 S 55 | |
|---|---|
 55 S 55 with training ammunition | |
| Type | Anti-tank weapon |
| Place of origin | Finland |
| Service history | |
| In service | 1955–1990s[1] |
| Used by | Finland |
| Production history | |
| Designer | Esko Puronto Kaarlo Sarkimo |
| Manufacturer | FDF Vammaskoski factory Ammus Oy |
| Produced | 1954–1970s[1] |
| No. built | >10,000[1] |
| Specifications | |
| Mass | 8 kg (18 lb)[2] |
| Length | 940 mm (3 ft 1 in)[2] |
| Cartridge | HEAT grenade with 300 mm (12 in) RHA penetration[2] |
| Caliber | 55 mm (2.2 in) (tube) 89 mm (3.5 in) (HEAT round)[2] |
| Action | Single shot |
| Rate of fire | 3 to 5 rounds per minute[2] |
| Muzzle velocity | 160 m/s (520 ft/s)[2] |
| Effective firing range | 300 m (330 yd)[2] |
| Maximum firing range | 700 m (770 yd)[2] |
| Sights | Optical, 4x |
55 S 55 (from Finnish 55 millimetrin sinko vuodelta 1955, '55 millimetre recoilless anti-tank weapon model 1955'),[2] colloquially kevyt sinko and nicknamed Nyrkki,[3] was a Finnish recoilless anti-tank weapon from the mid-1950s. The 55 S 55 was designed by a Finnish Defence Forces team led by MSc, Capt Esko Puronto, and it was manufactured by FDF's Vammaskoski factory (now part of Finnish state military industrial enterprise Patria).[3]
- ^ a b c "Konepajaosasto 1950—1980". lonnstrominmuseot.fi (in Finnish). Teresia ja Rafael Lönnströmin Säätiö. Archived from the original on 13 May 2019. Retrieved 31 January 2020.
- ^ a b c d e f g h i Panssarintorjuntaohjesääntö: Osa 1 (PstO I), Kevyt sinko (in Finnish). Finnish Defence Forces HQ (Pääesikunta). 28 June 1960.
- ^ a b Piesala, Aki (16 October 2018). "Lääkkeitä panssarintorjunnan kriisiin : Panssarintorjunta-aseiden hankinnat ja kehitys Suomessa 1948-1968" (PDF). utupub.fi (in Finnish). University of Turku. Archived (PDF) from the original on 31 January 2020. Retrieved 31 January 2020.