An inverse-geometry volumetric CT (IGCT) system uses a large source array opposite a smaller detector array. Conventional 2D IGCT reconstruction is performed by using gridding. We describe a 2D IGCT reconstruction algorithm without gridding. The IGCT raw data can be viewed as being composed of many fan beams, each with a detector at its focus. Each projection is undersampled but the missing samples are provided by other views. In order to get high spatial resolution, zeros are inserted between acquired projection samples in each fan beam, and reconstruction is performed using a direct fan beam reconstruction algorithm. Initial IGCT reconstruction results showed ringing artifacts caused by fact that the rho samples in the ensemble of views are not equally spaced. We present a new method for correcting the errors that reduces the artifacts to below one Hounsfield Unit.