Abstract: A grenade round 10 comprises a projectile 12, a case 14 and a high-low propellant propulsion system 16. The system 16 includes a propellant chamber assembly 30 for holding a propelling charge 32. The assembly 30 comprises a chamber body insert 38 which defines an internal cavity and a base plate insert 42 which closes off the internal cavity. The insert 38 is screwed into the case, while the insert 42 is screwed into the insert 38. The insert 42 defines a circumferential flange 60 which extends beyond and abuts a rim formation of the insert 38. The inserts define a high strength housing for the propelling charge which is able to withstand the high pressures resulting from combustion of the propelling charge. The flange provides a relatively large area for dissipation of energy resulting from combustion of the propelling charge, into the interface between the base plate insert and the case.

Abstract: A grenade round 10 comprises a projectile 12, a case 14 and a high-low propellant propulsion system 16. The system 16 includes a propellant chamber assembly 30 for holding a propelling charge 32. The assembly 30 comprises a chamber body insert 38 which defines an internal cavity and a base plate insert 42 which closes off the internal cavity. The insert 38 is screwed into the case, while the insert 42 is screwed into the insert 38. The insert 42 defines a circumferential flange 60 which extends beyond and abuts a rim Connation of the insert 38. The inserts define a high strength housing for the propelling charge which is able to withstand the high pressures resulting from combustion of the propelling charge. The flange provides a relatively large area for dissipation of energy resulting from combustion of the propelling charge, into the interface between the base plate insert and the case.