normal.... especially if they are the seedless variety.

Key limes are smaller than a ping pong ball. About 1" and takes forever to juice.

Denise,

If they are the seedless variety, try doing whole fruit juice instead of trying to squeeze them for the juice. This especially works well for things like key lime pie... no need to add zest, it is already there with whole fruit juice. I do the same thing for my Mayancello (limoncello made with fresh Meyers); because the peel of the Meyer is not bitter; and the whole fruit juice includes the oil from the peel.