The Obukhovskii 12"/52 Pattern 1907 was designed to reflect lessons learned from the
Russo-Japanese War and despite changes in specifications while the guns were being manufactured they were considered excellent pieces. In April 1906 a conference of twenty admirals and specialists in ship and ordnance design met to determine what the specifications of the new fleet being built to replace the
losses suffered during the Russo-Japanese War would be. The consensus of the meeting was that the new battleships would be armed with no less than twelve 12in guns mounted on the ships centerline and capable of delivering a twelve gun
broadside. This would be superior to any foreign ships then in service or under construction. Four triple
turrets were chosen for the new guns, because six double turrets would have made the ships too long for existing
slipways. Design sketches in early 1907 showed that triple turrets would save 15 per cent in weight over double turrets. These triple gun turrets were designated "MK-3-12", and were deployed aboard the
Gangut-class and
Imperatritsa Mariya-class and installed on the (although her propulsion was never installed and she was never completed)
dreadnoughts in mountings constructed by the
Metallicheskii Works. The gun originally envisioned was 12in/50 caliber, weighing , with a shell, at a muzzle velocity of . These new guns were to be based on the
12in/40 Pattern 1895 guns as used on the
Andrei Pervozvanny-class battleships. Since the requirement for new battleships was so urgent, work began before range testing could determine the appropriate shell weight, muzzle velocity or chamber pressure for the new guns. In July 1906 the Obukhovskii Works began production on the now 12in/52 caliber guns, with the inner tubes of the first guns being completed by the end of 1906. Between the project approval in 1906 and the final approval of ordnance specifications in 1911 the weight of shell, muzzle velocity and chamber pressure had changed multiple times. Since the inner tubes had already been built it was impossible to lengthen the guns to suit the new specifications. After the specified changes were implemented a shell with a muzzle velocity of and a weight of was settled upon (muzzle velocity being traded for increased shell weight). The Naval Ministry ordered 198 guns and somewhere between 126-144 had been produced by the end of 1916. Another twelve of the forty two scheduled were delivered in 1917. Fourteen incomplete guns were finished in 1921 and a few others were later completed. ==Construction==