| Siege gun|
combat: 5,300 kg
| Russian Empire|
| Horizontal sliding block|6-inch siege gun M1877 Wikipedia
6-inch siege gun model 1877 (Russian: 6-дюймовая осадная пушка образца 1877 года) was a Russian 152.4 mm heavy siege gun. The gun was produced by Obukhov Steel Works in Saint Petersburg. It was utilized in Russo-Japanese War, World War I, Russian Civil War and some conflicts of the early 20th century where former parts of Russian empire were involved. The only surviving piece is displayed in Hämeenlinna The Artillery Museum of Finland.