The frictional characteristics of a fine-sand and medium-sand slurry were evaluated experimentally in a 0.1 m diameter pipeline loop system at the GIW Hydraulic Test Laboratory. The median particle sizes were 85 and 400 μm. For velocities of practical interest in the interval 1.5 to 3 m/s, and volumetric concentrations of solids from 12 to 34%, the fine-sand slurry behaved essentially as an equivalent fluid. With the medium sand at 17% concentration, the excess losses over those of water were high at low velocities, decreased with increasing velocity and dropped below the equivalent-fluid curve at about 4.2 m/s. This behaviour was related to an inertial hydrodynamic lift force that is effective in driving particles in the medium-sand size range away from the wall. A lift coefficient is defined for the inertial lift force associated with the log-law turbulent velocity profile. In the buffer zone nearer the pipe wall, it is proposed that this lift diminishes in a way that depends on a dimensionless ratio that includes the particle radius and the shear velocity. This trend is seen to be in general agreement with both the medium-sand and the fine-sand data.