some hatcheries have this info
This site says the weight of egg size for each breed regular or bantam (((but info was from another country)))
http://www.kippengrabbelton.be/engels/
I call Meyers hatchery and asked them egg size for bantams
They gave me sizes for there hatchery ((he said all hatcheries have different strains so they have different sizes!))

This site says the weight of egg size for each breed regular or bantam (((but info was from another country)))
http://www.kippengrabbelton.be/engels/
I call Meyers hatchery and asked them egg size for bantams
They gave me sizes for there hatchery ((he said all hatcheries have different strains so they have different sizes!))