TYPE Flattened Spherical Double Base Powder BURNING RATE Medium / Fast PERFORMANCE BENCHMARK Winchester 231 and 450 APPLICATION Best suited to cartridges with medium/ low pressures and medium recoil for paper targets. BEST USED FOR 6,35 Br.; 7,65 Br.; 32S&W Long; 9 Corto ; 9x19 ; 9x21; 38 Special; 40 S&W; 45 ACP; 45 Long Colt. For mid range cartridges to be used in the following calibers: 44 Magnum; 41 Magnum; 357 Magnum.