The 2A42, 2A38, 2A38M, and 2A72 fire percussion-primed ammunition; the naval and aerial cannons use electrical priming, and therefore their ammunition is not interchangeable with the land-based ammunition types, despite the same cartridge case size.
Certain firearms, such as the 2A42, 2A38, 2A38M, and 2A72, employ percussion-primed ammunition. In contrast, naval and aerial cannons rely on electrical ignition, resulting in non-interchangeable ammunition with land-based types despite their identical cartridge case sizes.