It is the sound of two 23 mm NR23 cannon from the MiG15 cockpit. Russian MiG-15, Lavochkin La-15, MiG-17, and some models of the MiG-19, Ilyushin Il-28 and Beriev Be-6 use NR23 cannon. In MiG15 these cannons were placed more closely together in their undercarriage.

The MiG15 NR23 Cannon Sound consists of the looped audio file 8 seconds long and the ending file, which should be played at the end of the shooting. The WW2 Weapons SFX Library library includes 28 audio files.