Patent ID: 6223643
Filing Date: 2001-05-01
Classification: F41A

Abstract:
In a gun comprising a barrel having a rear end defining a firing chamber and the chamber having an obturation seat, and a breechblock;an obturation assembly comprising:an obturation set including an annular obturator pad for sealing against the obturation seat;an obturation spindle having a shaft and a head, the shaft extending coaxially through the obturator pad;a first shim for location between the obturation set and the breechblock; anda second shim for location between the obturation set and the head of the obturation spindle;the first shim is one of a first set of shims having different respective thicknesses and the second shim is one of a second set of shims having different respective thicknesses; each of the shims of the first set being associated with a respective one of the shims of the second set, for enabling a user to select a suitable pair of associated first and second shims for a particular position of the obturator pad relative to the breechblock.