i have run most powders out of mine i started with a 26" barrel and then rebarreled to 32". my top 4 depending on what im shootin are n570, rl33, lrt, retumbo. i shoot 225g eldm, 230atip, 230 hybrid, 250atip. throated for the 250's and it loves them with n570 or lrt the others get retumbo or rl33