A subterranean screen system features openings in a base pipe and sleeve sections of a porous material that preferably swells in the borehole to span an annular space around the base pipe. Retainers are mounted to the base pipe in a desired location and mechanically fixated using an internal grip system actuated through the wall of the retainer. A wedging action of slip segments is initiated by an angularly advancing assembly through the wall of the retainer. The retainer can have end rings extending past one or both ends over which the screen sleeve extends. Flat or ridges on the exterior of the retainer or end rings make assembly easier with hand tools to allow for rapid field assembly, if needed. Filtration occurs through the sleeves that abut the borehole wall and into the base pipe openings and to the surface.