Abstract: A cartridge casing collector, for use with rifles of the type having a cartridge casing ejection port in connection with the exterior of the rifle, including a housing member having a collecting chamber formed therein in communication with a casing receiving aperture, and a spring loaded gripping assembly secured to the housing assembly for securing the casing receiving aperture over the ejection port of a rifle in a manner such that cartridge casings ejected from the ejection port are directed through the cartridge casing receiving aperture and into the collecting chamber. The collecting chamber is at least partially defined by an interior surface having a radius of curvature between three and one-eight (3-1/8") and five and one-half (5-1/2") inches and a length corresponding to an arc of at least thirty (30.degree.) degrees of the radius of curvature.