<p>Barrel markings for Russian 152,4 mm (6 inch) 190 pood M 1877 fortification gun (осадная пушка), displayed in Hämeenlinna Artillery Museum. This gun was manufactured by Obukhov in 1881.
Photo taken on June 18, 2006.
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Source: Photo by me, <a href="//commons.wikimedia.org/w/index.php?title=User:Balcer&amp;action=edit&amp;redlink=1" class="new" title="User:Balcer (page does not exist)">User:Balcer</a>.
<a href="//commons.wikimedia.org/wiki/User:Balcer~commonswiki" title="User:Balcer~commonswiki">Balcer~commonswiki</a>
CC BY 2.5
<span class="int-own-work" lang="en">Own work</span>