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I have read, on one of the old gunboards, that the compressed black powder pellet for the .303 had a hollow core molded in for more complete ignition.
Cordite "load data" was in the form of strand diameter, number of strands, and the length of bundle to the nearest 1/20 th inch. The reel of Cordite was in a separate room, feeding out through a small hatch to the loading room where it was cut to length and dropped in the unnecked shells.
It is a very efficient propellant but erosive to barrels. Production went from Metford rifling, rounded like Glock "polygonal" to a strong 5 groove layout, Enfield pattern. That helped but erosion was still bad so they revised the formula and reversed the proportions of nitroglycerine and nitrocellulose. This was Cordite MD for MoDified. Or is that ModifieD? I can't figure which.
Even with those changes there were cautions about changing from Cordite to nitrocellulose, identified in British military .303 with a "Z" suffix. One should not use a machine gun for overhead fire with Cordite if it had been shot with nitrocellulose. Or maybe the other way around, but the wear patterns were different and could cause wild shots.
Revolver Cordite was just regular Cordite chopped into short granules.
At one time the .458 Win Mag got a bad reputation in Africa. Meant to equal the ballistics of the .450 Nitro Express, it got close with a compressed powder charge and a 25" barrel. When Winchester shortened the barrel to a handy 22" and fudged the load so that overcompressed powder did not pop the occasional bullet out, velocity dropped below 2000 fps. Some PWHs found that inadequate and turned to handloading. They found that Cordite from pulled down .303 got the .458 up to where it was supposed to be. Hot stuff.
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