The .303 was not " of the smokeless age " , it was the last of the black powder age . All the other cartridges listed were designed as smokeless rounds . The original .303 bp round of 1888 - 95 [ 215 grains at 1850 fps ] compared poorly to the other smokeless rounds of the same era . German 7.92 - 224 rn at 2100 , 8 Lebel - 198 spritzer at 2240 , 30/40 Krag 220 rn at 2200 and so on . When the British finally went to smokeless [ cordite as their black powder bridge locking action was too weak for nitro powder ] their load of 174 at 2380 was by far the weakest of at the .300 - 311 bore rifles at that time . German 7.9mm - 154 at 2880 , 7.62x54r 147 at 2880 , 30/06 - 148 at 2780 , the Swiss were limited to a 174 at 2560 because of their SR 1911 actions . The post WWI cartridge designs were changed for certain objectives . The German went to 198 btsp machine gun ammo for the rifle , the French wanted an intermediate round , the 7.5 - 139 at 2640 , the Japanese wanted close to the bullet weight and dia of the 8x57mm they were against in China , so they necked the 8x57 down to 7.7 [ as they were already making a 7.7 machine gun barrel and bullet ] and down loaded it for their smaller troops . The British updated the .303 with every trick they could to get it closer to all the other rounds . Went with the 174 as they could not get any more cordite in the case for a higher velocity lighter bullet , a .3095 dia lubed bullet in a .313 ++ groove to get as much velocity with lower pressure , a light tip to help it tumble for more hitting power . They really wanted to modernize their rifle and cartridge in 1913 , but
WWI stopped that .