And another point, you don't always get enough pullets! Last year I hatched out 11, got three pullets. I have been doing chickens for years, but until this year, I have had to add chickens, or chicks, or eggs from outside of my flock into it. It sounds easy to be sustainable, but it is a bit more tricky than you might think.
Mrs K
We started a self-sustaining flock of Black Java's in April 2010. Bought 9 chicks - one turned out to be rooster, all's well. Purchased in April 2010, started laying in September, went broody in May/June 2011.
2011's first year's chicks all but one killed by an owl at about 16wks old. Grrrr.....had eight of eight broody hens. Didn't have eggs again until September!
Third year (2012), had 17 chicks hatch from those eight broodies. 13 were cockerals!
Determined we needed more homegrown meatbirds - raised Red Rangers. Nice birds, tasty, easy to take care of - meat lasted longer, as we raised 25. Just need big freezer to do this!
Fourth year (2013), had 10 broodies with 21 chicks, 11 hens! Ate the boys.
Raised Cornish X meatbirds. Hated them. Loved the meat, disliked the birds. Raised 25 birds.
Now on our sixth year, they've slowly increased the egg flock to larger than it likely should be - and the quantity of broody hens has remained the same. Yes, they've changed who's broody - but of our hens, not more than 1/3 are broody any given year. And yes, our original birds are still with us (all but one, killed by hawk). And yes, those original birds still lay and are more likely to go broody also. They're great momma's, even if they're starting to slow down a bit.
My point is - even if you have a dual purpose bird, it takes much too long to actually develop a self-sustaining flock, as most birds will only be broody once a year (spring/summer) - and there's simply no way around that. Now, if I managed the flock for purely our consumption, I would keep a stable flock of 9 hens, 1 rooster and eat the cockerals produced and replace the hens fairly frequently.
But that does not take into consideration that a flock is an organic component of individual, social creatures. When an owl killed one of a sister pair - the sister called for literally days afterwards trying to find where her sister had gone to. (She actually went hoarse calling for her sister). How can I cull birds willy-nilly based on production alone? Are there other factors to consider? And why do the cockerals know when it's time to select a new rooster? And how do they know none of them are the one to be selected? (We buy a new rooster every year from the farm they came from - over 100 trios of birds to mix the gene pool around). I cannot explain it. But they know.
Figure out what you are seeking - we wished meat birds - we order 25 chicks, grow them, send them to Camp Frigidaire, and enjoy what they offer us. We need egg layers - they have allowed us to give eggs to families in need, to the elderly we know and help others. Being able to enjoy our cockerals at our table has been extra - we do not count of it, but rather thank God for the provision, as we never know how many cockerals are under those broodies! Should we cull our main flock now that it's so big? Likely. Just a matter of time. But I'm taking my time watching the hens, seeing who's who and deciding what to do - this is a life we've taken care of from the start. I wish to honor that.
Good luck on your journey!