Can someone tell me the ideal weight or age to slaughter the Barred Rocks?

thanks
RM

It is what weight you like, not age. All birds will not reach the same weight at the same time. I like mine to dress out at 4 pounds or over, but lots of people like 1 1/2-3 pounds. I always cut and package in parts. Others package whole birds. It's whatever you want. CJR

we have barred rocks and when we started cooking them we found out that the legs are REALLY tough

Traditionally, dual purpose birds were dressed out at 12 weeks as fryers. This gave a bird with some size, but not too much toughness. Since all the commercial frying chicken we eat today is Cornish X, we have become spoiled into thinking that big chickens can be tender, and that is true if they're Cornish X. In the old days, 12-week old fryers were about all we knew, so they seemed pretty tender, too. If you go much past 12 weeks on your Rocks, I think you will find that you will have to settle for soup rather than fried chicken.