The cartridge employs a captive piston, creating a gas seal, so there is no flash or loud report upon discharge.

The OTs-38 revolver is claimed to be effectively silent, as the sound level of the live and dry firing is practically identical.

This system is virtually identical to that employed by the Quiet Special Purpose Revolver (QSPR) a variant of the commercially available Smith & Wesson Model 29 .44 Magnum revolvers, rebuilt to fire specially manufactured dedicated integrally silenced ammunition: Early prototypes had very short smooth-bore barrels with 0.40 inch (10 mm) bore and matching chambers, but later versions have longer barrels of up to four inches (100 mm).

This load was tailored to wound at up to 100 ft (30 m), and have a practical, and potentially fatal, effect at ranges below 30 ft (10 m), deemed sufficient for the QSPR's intended and narrow application: clearing the confined and dimly lit to pitch-black tunnels encountered by “tunnel rats" during the Vietnam War.

In contrast to its virtually stock predecessor, the later OTs-38 is innovative to a degree unusual even in special purpose weapons: The OTs-38 is fitted with an integral laser sight located above the cylinder axis (where a conventional revolver has its barrel) powered by three D-0.03D batteries.