ENCAPSULATED CASE FOR SMALL ARMS Russian patent published in 2017 - IPC F42B5/26 F42C19/10 

FIELD: weapons and ammunition.

SUBSTANCE: case has a central hole in the chamber of cap well bottom and a circular recess on the peripheral part of the cap well bottom and a cap primer pressed into it consisting of a metal cap with a pressed into the percussion ignition composition coated with a sealing membrane. Instead a trilobal anvil, a metal ball is applied adjusting with one side to the sealing membrane and with the other—to the case cap well bottom partially being located inside the central hole of such diameter that the metal ball is recessed into the cap well relative to cap head end by an amount "D" equal to the value "C" of the maximum height of the igniter composition with a sealing membrane with account of tolerance, plus an amount of the metal cap wall thickness plus the value "N" specified for the cartridge acording to depth of the cap primer relative to the cap head end within the tolerance. The "A" value of cap well depth is equal to the "B" value of the metal cap height within a tolerance plus the "H" value defined according to the recess of the cap primer with respect to the cap head end within the tolerance. So, the formulas should be implemented: "A"="B"+"C" and "D"="C"+"N". Thus, two or three symmetrically arranged around the circle through holes are made peripherally the cap well bottom.

EFFECT: increased reliability and sensitivity of the cap primer triggering.

3 cl, 1 dwg