Bigger bread

Hi all, i have been making a standard no knead bread for sometime now and all is well. I have tried recently to make a bigger loaf buy doubling the ingredients but they have come out quite doughy.
I have increased the bake time from 30 mins to 50 mins but left the dutch over open time to the same as the normal bake but it it still a little doughy.
Should i increase the bake time more or the open bake time more to dry the bread

You might find some useful info in this thread. Good luck!