Accroding to Do-It-Molds they weight them without a hook. mpossible to get the actual weight then. Then you have different hook types, different alloys and so on and you get different weights.

But as said, what does it matter, find the size you catch fish with and use it. 1/80 and under the head is more to allow a small bead to make it easier to tie a nice body on, lol. Makes it easier than wrapping the shank with lead wire or something else to give it some weight.