We report the efficient gain-switched high-repetition-rate Cr2+:CdSe single-crystal laser operating around 3 μm and pumped at 2.09 μm by a fiber-laser-pumped Ho3+:YAG laser. Average power of up to 6 W with the optical-to-optical efficiency of 67% at 2.65-2.85 μm was achieved in the Cr2+:CdSe laser with nanosecond pulses at 8 kHz repetition rate. Wavelength tunability from 2.5 μm to 3.15 μm was demonstrated using a set of cavity mirrors and an intracavity Lyot filter.