yes they will!! I cant believe sometimes, how big a chick is that pops out of the smallest egg. and the legs on them! I had one pip thru the very end of the egg, right thru the air cell, I figured it wold drown and not make it, it was an egg from the marc sacre pullet. I was so bummed... it stayed like that overnight and half the next day but could see a tiny piece of shell moving in and out so I left it alone, was watching one hatch and suddenly that one, with no zipping at all, gave a mighty shove and popped the entire end of the egg right off and tumbled out! haha I was shocked! mostly because I have never seen one not zip and secondly because I was watching when it did it. I stared at it until it was a little stronger, grabbed it quick and banded it and put it back, I DID not want to lose track of that one lol. it was huge too, hope its a cockerel !