As part of a research program, it was desired to better understand the impact of the rotatingchamber alignment with the barrel throat on the precision and accuracy of a novel CasedTelescoped (CT) ammunition firing rifle. In order to perform the study, a baseline CTammunition chamber which was concentric with a Mann barrel bore was manufactured.Additionally, six chambers were manufactured with an offset relative to the barrel bore.These chambers were used to simulate a misaligned chamber relative to the bore axis.Precision and accuracy tests were then performed at 200 m in an indoor range undercontrolled conditions. For this project, 5.56mm CT ammunition was used. As the chamberaxis offset relative to the gun bore was increased, the mean point of impact was displacedaway from the target center. The shift in the impact location is explained by the presence ofin-bore yaw which results in lateral throw-off and aerodynamic jump components. Thelinear theory of ballistics is used to establish a relationship between the chambermisalignment and the resulting projectile mean point of impact for a rifle developed to fireCT ammunition. This relationship allows for the prediction of the mean point of impactgiven a chamber misalignment.
展开▼
