For reloading Berdan brass caliber 577NE, i use TU3000, about similar to IMR3031, same load that the original cordite load, 90gr.powder and 750gr.FMJ bullet, and i use a 0.5" wad! I had a bad experience by the ignition of R15 in Berdan cases. I think in Boxer cases, no problem. But carefull, we do that under our responsability!