I've got 2 BR's and a SS they all started laying Friday. I've since got an egg a day since then, and today I've got 2 so far. The eggs are very tasty but tiny. How long does it take until they start to lay full size eggs?
I agree, give it about a month and you should see the size of the egg getting toward the top size for the breeds you have. The operation internally will get into full swing and the vent will expand.
And at the end of the month, if they are still tiny, don't worry... I've been getting pullet eggs from one of my girls for 2 months!!!