I love barred rocks!
I have 2 3 week olds. Wait a couple more weeks until they start feathering in and post again. I have 1 pullet and 1 cockerel. I will post pics of mine so you can see the difference. The pullets feathering looks more "speckled" at this age and the cockerel has larger barring Making it look like its thicker white.
Also you can notice my cockerel from the comb difference. Hope this helps!
2nd pic is my cockerel 3rd is the pulletEdited by Madisan - 11/15/15 at 2:56pm