Same size, in fact on the smaller end of the 6. The only one markedly bigger is the Easter Egger and I feel like she must have been a day or two older than the others since they were delivered at supposedly 3 days old by the time they got to the post office. The size difference between the EE and the others has been shrinking slowly over the 3 weeks.
The other thing about this BR is this chick has gotten every single one of the 5 or 6 daddy long legs I’ve dropped in the coop and run. The others don’t stand a chance when Buffalo spots a moving critter.
I am watching chicken TV while they enjoy some Run time before I kick them back to the coop, don’t trust them to go back and forth by themselves in inclement weather until they are feathered out. Just now she was eating out of the food dish and another chick dig up some sort of insect that was about 2” long, made a “I found food!!” Noise and within 5 seconds the BR had it and just devoured it. This chick is crushing the others’ dreams of having some live food snacks!