Cartridge chamber and breech unit for rifles

Claim 1

In a rifle, cartridge chamber-forming means in the form of an elongated tubular body formed with an axial bore extending completely therethrough and terminating in a rear end face normal to the axis of said bore, said body also having forwardly of said rear end face a rearwardly directed surface surrounding the axis of said body, said body being formed with a groove extending rearwardly from said rearwardly directed surface and at least partly surrounding said axis and said body having between said groove and said rear end face an outwardly directed flange conforming to the configuration of and extending along said groove with the latter extending between and being defined at its opposed side surfaces by said rearwardly directed surface and said flange, a breech unit having a front end surface slidably engaging said rearwardly directed surface and, to the rear of said front end surface, a forwardly directed surface slidably engaging said rear end face of said tubular body, said breech unit being formed with a groove extending forwardly from said forwardly directed surface thereof and matching the configuration of said flange to receive and be filled by the latter and said breech unit having forwardly of said groove thereof an inwardly directed flange extending from said groove thereof up to said front end surface and matching the configuration of said groove of said tubular body to be received in and to fill said groove of said body, said grooves being respectively filled by said flanges when said breech unit is in a closed position closing said bore, said front end surface of said breech unit and said rearwardly directed surface of said tubular body forming a pair of surfaces slidably engaging each other and one of which is formed with an arcuate groove while the other of which carries an arcuate rib slidably received in said arcuate groove for guiding said breech unit for swinging movement transversely to the axis of said bore between said closed position and an open position uncovering said bore at said rear end thereof so that a cartridge may be inserted into said bore, and said front end surface of said breech unit and rearwardly directed surface of said tubular body also forming a pair of surfaces one of which is formed with an arcuate groove and the other of which carries a pin which is received in said last-mentioned arcuate groove to limit the swinging of said breech unit with respect to said tubular body to an extent which will uncover said bore when said breech unit is in its open position and which will close said bore when said breech unit is in it is closed position, at least said tubular body being formed at an exterior surface region thereof with an indentation and said breech unit carrying a swingable lever having a tooth received in said indentation when said breech unit is in said closed position for releasably holding the latter in said closed position until said lever is turned to a release position displacing said tooth out of said indentation to thus release said breech unit for swinging movement from said closed to said open position thereof.