METHOD COMPLEX IMPROVEMENT OF FIRE QUALITIES OF RIFLED GUN AND ABRAMYAN'S RIFLED BARREL FOR SAID GUN Russian patent published in 2013 - IPC F41A21/18 

FIELD: weapons and ammunition.

SUBSTANCE: barrel comprises bore with helical rifles and intermittent inclined and/or lengthwise-inclined grooves. Said grooves continuously cross the rifles at depth equal to rifle depth. Projection of intermittent groove length on barrel lengthwise axis is smaller than bullet lead part length. Intermittent recesses are made at barrel end between rifles. Wall of said recesses are perpendicular to powder gas jet. In fire, air is displaced in free space behind the shot and passed between bullet and bore surface via intermittent recesses in case air pressure exceeds that of compressed air nearby bullet shoulder while, on the contrary, compressed gas is displaced via intermittent and/or continuous inclined-lengthwise recesses. Air pressure is additionally increased in overlapping bullet lead grooves.

EFFECT: higher initial velocity and accuracy of hits, smaller recoil, barrel heating and lower shot sound level.

4 cl, 12 dwg