We report on narrow-linewidth long-pulse laser emission from a dispersive solid-state dye-laser oscillator. Output energy was ~0.4 mJ/pulse at laser linewidths of 650 MHz and pulse lengths of 105 ns FWHM. The solid-state gain medium utilized was Rhodamine 6G dye-doped 2-hydroxyethyl methacrylate:methyl methacrylate.