The smooth-bore Vepr-12’s inherited the general configuration of machine gun (RPK) Kalashnikov, with gas venting mechanism and locking bolt carrier. Naturally, carrier group and a receiver were redesigned. Aiming adaptations from Kalashnikov AK, with adjustable front and rear sight installed on the gas tube. The receiver cover is hinged and opens up-forward, as on the AKS-74U machine gun. In addition cover of a receiver has welded Picatinny rail allowing for fast and convenient installation of various optical sights.
Feeding of ammunition is accomplished by utilizing plastic single-row magazine with a capacity 4-8 cartridges, bolt hold lock system was integrated in all shotgun configurations, allowing for bolt carrier to be locked in open position after discharging last round (for quick magazine reloading). Butt stock is metal, skeletal design with rotating sideways cheek rest. Outside the buttstock is covered with plastic for comfort of firing in hot or cold temperatures. Hand guard and gas tube has an additional directional Picatinny rail for installation of laser, tactical light or any other accessory.