The development of an electron-beam initiated HF (H2/SF6) laser is described. Typical parameters of the circular electron beam used in the experiment are 2 MeV, 80 kA, 65 ns (FWHM), and 9 cm in diameter. The maximum laser energy of 250 J in a 70 ns FWHM pulse is obtained with an electrical efficiency of 8.3% at SF6/H_2=200/2 (Torr). Initiation parameters are determined by theoretical HF laser simulation, such that the dissociation rate, the energy cost per F atom and the chemical efficiency are 3%, 6.5 eV/F, and 39%, respectively.