This paper presents a benchmark performed in the frame of the SARNET-2 EU project, dealing withmomentum transfer between a real-scale PWR spray and the surrounding gas. It presents a descriptionof the IRSN tests on the CALIST facility, the participating codes (8 contributions), code-experiment andcode-to-code comparisons. It is found that droplet velocities are almost well calculated one meter belowthe spray nozzle, even if the spread of the spray is not recovered and the values of the entrained gasvelocity vary up to 100% from one code to another. Concerning sensitivity analysis, several 'simplifications'have been made by the contributors, especially based on the boundary conditions applied at the locationwhere droplets are injected. It is shown here that such simplifications influence droplet and entrained gascharacteristics. The next step will be to translate these conclusions in terms of variables representativeof interesting parameters for nuclear safety.