In 1994 the Tula-based KBP Instrument Design Bureau developed its own more powerful version of the 12.3 mm Udar revolver, designated U-94. The revolver featured the same design as the R-92 with a solid streamlined frame, a swing-out cylinder, and a single-action/double-action trigger assembly. A family of various 12.3x50 cartridges was based on the brass 32-gauge shotgun cartridge.
Cartridges are loaded into the cylinder with the he5p of a cip consisting of two disks with holes for rounds. The clip can also be used for simultaneous extraction of spent cases. Besides the caliber and dimensions, this Udar model differs from the R-92 in the shape of the trigger guard designed for two-handed firing.
There are also the Udar-S (U-94S) "service55 (weaker) model, chambered for the 12,3x22 (PM-32) cartridge, the Udar-TS (U-94TS) training version chambered for 12.3x40 cartridges (KP-32 paintball rounds or rubber baton cartridges), and a non-lethal version available on the market under the name of "Ratnik".