7.62 mmm TT wz.33

This is not revolver. This is pistol 7,62 mmm TT wz.33

Thanks Polar, titled changed

The TT-30 (Russian: 7,62-мм самозарядный пистолет Токарева образца 1930 года, translit. , 7,62 mm Samozaryadny Pistolet Tokareva obraztsa 1930 goda, "7.62 mm Tokarev self-loading pistol model 1930", TT stands for Tula-Tokarev) is a Russian semi-automatic pistol. It was developed in the early 1930s by Fedor Tokarev as a service pistol for the Soviet military to replace the Nagant M1895 revolver that had been in use since Tsarist times, though it ended up being used in conjunction with rather than replacing the M1895. It served until 1952, when it was replaced by the Makarov pistol.

Poland produced their own copies as the PW wz.33, manufactured from 1947 to 1959.
https://en.wikipedia.org/wiki/TT_pistol