when to go 12 on 12 off

Depends. It's a matter of personal preference, how fast your meaties are growing, and what you are feeding them. A lower protein feed will slow down growth anyways, so restriction is not as important. Also, if you have a slower growing group, I would think that free choice shouldn't be a problem. And some people have a routine, a certain age at which they always go 12/12, or will only feed so many pounds of food a day (and not refill it till the next day). So really it's up to you, and what you think is right for your chickens.

If you want to see what others are doing, a group of us are doing a meatie weigh along, and comparing management styles. We've seen % protein and restriction really impact the rate of growth.
https://www.backyardchickens.com/forum/viewtopic.php?id=477241

 

I start restricting at 2 weeks.

 

i start at 2 weeks, that seems to be when they start really putting on weight. but if their legs seem to be restricting their movement - start a bit earlier.

 

Quote:A 12/12 lighting program is entirely wrong.
Here are the recomendations of the breeding company that provides the genetics for most of the broiler chickens produced in the world. This probably includes the hatchery you bought your chicks from. But it makes no difference since no matter what genetics provider the recomendations are about the same.

Go to-

http://www.cobb-vantress.com/contactus/brochures/Broiler_Mgmt_Guide_2008.pdf

Read sections 5.3 & 5.4

I know that many hatcheries recomend 12/12. I imagine that they are just telling you what you expect to hear. Just like the chicks being Cornish and Rock crosses. No meat chicken genetics provider ever refers to Cornish or Rocks in their product description.

 

I have to agree with Neil Grassbaugh. I tried the 12 on 12 off once and they would trample one another to get to the food when that 12 hrs was over. One suffered a broken wing. That was enough for me. My feeders are full all the time. Good luck to you however you do it.