I don't know about relative juice capacity on the basic standard cartos ( a 510 std holds about 25drops), but you can get longer (xl) sized 510 cartos that can hold about 55 drops of juice. There are many styles available, but some require a higher capacity battery, such as an eGo. I use XL sized dual coils on an eGo or my Roughstack or an ugly box mod, as they require more mah than a 510.
I don't know if it helps, but some vendors sell adapters so you can use 808 cartos or atomizers on a 510 battery or vice versa. I got mine at Goodprophets so I could use our old 401 attys on a 510 battery for dripping to try new flavors. These are handy if you have a lot of pieces left to use up.
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Keep on digging here on ECF - it was my education on vaping and has saved me a lot of $.