| 15 cm sIG 33 | |
|---|---|
 A sIG 33 at the Belgrade Military Museum, Serbia | |
| Type | Heavy infantry gun |
| Place of origin | Weimar Republic |
| Service history | |
| In service | 1927–1945 |
| Used by | Nazi Germany |
| Wars | World War II |
| Production history | |
| Designer | Rheinmetall |
| Designed | 1927–33 |
| Manufacturer | Rheinmetall, AEG-Fabriken, Bohemisch Waffenfabrik |
| Produced | 1936–1945 |
| No. built | around 4,600 |
| Variants | sIG 33/1 |
| Specifications | |
| Mass | 1,800 kg (4,000 lb) |
| Length | 4.42 m (14 ft 6 in) |
| Barrel length | 1.65 m (5 ft 5 in) L/11 |
| Width | 2.06 m (6 ft 9 in) |
| Shell | cased separate-loading (6 charges) |
| Caliber | 149.1 mm (5.87 in) |
| Breech | horizontal sliding-block |
| Recoil | hydro-pneumatic |
| Carriage | box trail |
| Elevation | 0° to +73° or -4° to +75° |
| Traverse | 11.5° |
| Rate of fire | 2-3 rounds per minute |
| Muzzle velocity | 240 m/s (790 ft/s) (HE) |
| Effective firing range | 4,700 m (5,100 yd) |
| Sights | Rblf36 |
The 15 cm sIG 33 (schweres Infanterie Geschütz 33, lit. "heavy infantry gun") was the standard German heavy infantry gun used during Second World War. It was the largest weapon ever classified as an infantry gun by any nation.[1]
Its weight made it difficult to use in the field, and the gun was increasingly adapted to various ad hoc mobile mounting, which were generically referred to as the SIG 33.
- ^ Hogg, p. 26