One of our biggest Buff Orpingtons lays eggs 5-6 times a week that size, she has since she started laying. Hers are always huge double yolkers and we can hardly get them to fit in the large egg cartons, sometimes they are just too big to fit at all without leaving the lid open, so we have to put her eggs in a bowl. Lol, at first we were amazed but now it's expected. She did use to scream loudly when she laid them, but not so much anymore. They sure make a great egg sandwich!
