SILENT AND FLAMELESS FIXED ROUND Russian patent published in 2008 - IPC F42B5/02 

FIELD: ammunition.

SUBSTANCE: fixed round comprising a grenade body that is supported by a piston follower with a blind cavity limiting from above a propellant powder charge. Said charge is placed into a flange that is hermetically screwed with the case and wherein an initiator is secured. Inside the case shoulder there is a recess formed by means of two surfaces tilted respectively at an angle of 11° and 65° to the centre line from the neck side. The recess apex is disposed on a diameter adjusted to the outer diameter of the case neck. The piston at the follower side has the form of a cone, the generatrix of which is 21° tilted with respect to the centre line.

EFFECT: improving the functional reliability and purpose parameters of the round for covert launching of long-range grenades.

2 dwg