The range distributions of 10–120 keV11B+in polycrystalline Co, Ti, CoSi2, and TiSi2targets have been measured by secondary ion mass spectrometry. The obtained projected rangesRpand projected range stragglings &Dgr;Rpare within 25% and 10%, respectively, of those predicted using the Monte Carlo computer programtrim. By comparison the one‐dimensional Boltzmann transport calculation insuprem‐3 tends to overestimateRpby as much as 300% at the highest ion energies.