The performance of the XeF(C→A) laser, pumped at a rate of 290 kW/cm3with a 600‐ns electron‐beam pulse, has been improved through the optimization of the laser gas mixture and resonator output coupler reflectivity. An intrinsic efficiency of 1.1% and a specific output energy of 2 J/l have been demonstrated. A uniformly pumped region of the gain medium was selected for diagnosis in these measurements. In a separate experiment with larger diameter mirrors, a total output energy of 4 J was recorded. These are the highest specific and total output energies reported thus far for a directly electrically excited XeF(C→A) laser. The laser pulse duration was 350 ns (FWHM), and the laser bandwidth was 160 A˚. The small‐signal net gain was measured during the electron‐beam pulse at various wavelengths, and a peak gain of 0.4%/cm was observed. The sidelight fluorescence spectrum was also recorded.