| 16-inch gun M1919 | |
|---|---|
 16-inch gun M1919 on barbette mount M1919, Fort Duvall, Boston, Massachusetts. | |
| Type | Coastal Artillery |
| Place of origin | United States |
| Service history | |
| In service | 1920–1946 |
| Used by | United States Army Coast Artillery Corps |
| Wars | World War II |
| Production history | |
| Designer | US Army Ordnance Corps |
| Manufacturer | Watervliet Arsenal |
| Specifications | |
| Mass | 484 tons |
| Barrel length | 50 calibers, 66 ft 8 in (20.32 m) |
| Shell | AP: 2,340 lb (1,060 kg) or 2,100 lb (950 kg);[1] 850 lb powder charge[2] |
| Caliber | 16 in (406 mm) |
| Carriage | M1919 Barbette or M1917 disappearing, both fixed |
| Elevation | -7° to +65° (-5° to +30° disappearing carriage)[3] |
| Traverse | 360° (open and disappearing), 145° (casemated)[1] |
| Muzzle velocity | 2,700 ft/s (823 m/s) |
| Maximum firing range | 49,100 yd (44,900 m)[1] 27.9 miles (less with disappearing carriage) |
The 16 inch gun M1919 (406 mm) was a large coastal artillery piece installed to defend the United States' major seaports between 1920 and 1946. It was operated by the United States Army Coast Artillery Corps. Only a small number were produced and only seven were mounted; in 1922 and 1940 the US Navy surplussed a number of their own 16-inch/50 guns, which were mated to modified M1919 carriages and filled the need for additional weapons.