Sergei Korovin was a Russian designer who was kicked out of the Kharkov Technical Institute in 1905 for his revolutionary political activities. He emigrated to Liege in Belgium, where he worked in the arms industry until returning home to Russia when World War One broke out in 1914. He attempted to get a job at the Tula Arsenal, but was unable to do so until about 1920 (by which time his politics were presumably working in his favor). He went to work on handgun designs, and would produce the Tula-Korovin in 1926, the first Soviet production semiauto pistol.

Korovin’s first work was in 1923, on a short-recoil military sidearm in .32ACP, which would be modified to .30 Mauser by 1929, but ultimately lose out to the Tokarev TT-30. However, the Tula Arsenal opted to scale down his pistol in 1926 to a simple blowback .25ACP design, which was produced in large numbers between 1927 and 1935. It was made in three variations with apparently a total production in excess of 500,000. The third variation was beefed up a bit, and apparently chambered for a higher pressure version of the .25 ACP cartridge designated the 6.3mm Tula - although detailed information on this is difficult to find.