Can be found in Shotgun - Break Action.
A Soviet/Russian flare gun modified to fire 23 x 75mm that KS-23 fires. Modified mesh from dummy data found in Escape from Tarkov, which is originally a normal 26mm flare variant of SP-81.
23mm shotshell is already well known for its dumb punch. This gun fits in your magazine slots, essentially serving as a pocket KS-23 that can work as a last-ditch backup weapon, or a trolling device that will instantly pop a flashbang in sosigs' faces.
If needs arise might implement the flare version as well.
The SP-81 model is made by Battlestate Games, Escape from Tarkov. Ripped by Wolfie. Sounds are from Battlefield 1.
