21 cm RK L/19
              < 21 cm RK L 
 
            
          | 21 cm RK L/19 | |
|---|---|
| Krupp 21 cm RK L/19 gun on a broadside carriage | |
| Type | |
| Place of origin | German Empire | 
| Service history | |
| In service | cc 1870 | 
| Used by | |
| Production history | |
| Designer | Krupp | 
| Manufacturer | Krupp | 
| Specifications (L/19) | |
| Mass | 9,390 kg | 
| Length | 3.923 m (L/19) | 
| Caliber | 209.5 mm | 
| Breech | Horizontal sliding breech | 
| Muzzle velocity | 425 m/s | 
| Effective firing range | 3,750 m at 9.5° | 
The 21 cm RK L/19 was the later name of a rifled breech loader gun of the Prussian Navy. This gun started with a massive gun barrel, cast from steel in one piece. In 1868 a built-up gun barrel version was tested in Prussia and found to be much more powerful. Many of the massive guns were then changed to built-up guns. These changed guns became known as kurze Ring Kanone, and later as 21 cm Ring Kanone L/19.