| M256 | |
|---|---|
&sq=Qlik&lang=&file=File:A_day_in_gunnery_131206-A-CW513-121.jpg) Front view of a M256 gun on an American M1A2 SEP main battle tank during a gunnery exercise at Red Cloud Range, 2013. | |
| Type | Tank gun |
| Place of origin | United States Germany |
| Service history | |
| In service | 1985–present |
| Production history | |
| Designer | Rheinmetall Watervliet Arsenal |
| Manufacturer | Watervliet Arsenal |
| Produced | 1985–present |
| Variants | XM256, KM256, M256E1 |
| Specifications | |
| Mass | 1,175 kg (2,590 lb) (gun tube) 1,905 kg (4,200 lb) (recoiling gun mass) |
| Length | 5,593 mm (220.20 in) (overall) |
| Barrel length | 5,300 mm (208.66 in) (gun tube) |
| Shell | 120×570mm |
| Calibre | 120 mm (4.724 in) |
| Breech | semi-automatic vertical sliding-breechblock |
| Recoil | 304.8 mm (12.000 in) |
The M256 is an American 120 mm smoothbore tank gun. It is a licensed-built German-designed Rheinmetall Rh-120 L44 gun tube and combustible cartridges with an American-designed mount, cradle and recoil mechanism. It is primarily used by the M1 Abrams main battle tank.