buck shot
I recon you could say ''bigger buck for the bang'', i used to know all that stuff and probally could remember it if i tried, i.e. amount of shot in different guages and all that, but i like the trip-ot .000 in my .410, its like (and no, i didnt caliper it either) 3-.40cal. balls, but its close as hell range stuff , speaking of any kind of accuracy at all cause we blasted some .000 thru it and man that stuff went everywhere!, i mean absolutly no consistancy at all!, i mean NONE, by god. It also was pretty expensive too, i've still got a bunch of it upstairs, incidently, i dont even know if i have seen and .00 (double) in .410, i mean if it's out there i aint seen it, but they probally do, if it can be loaded into a shell or caseing someone will do it, and sell it of course. But to get back on trac as per your question .00 shot is bigger than .000 shot, or less pellets, whatever. see ya