Agreed.
Without taking into breed differences, the best indicator is the comb. Most males in most breeds get a predominantly pink-red comb around 8 weeks with signs usually sooner.
Ignore behavior. I've had plenty of snotty pullets especially in an all pullet batch. I've also had
Amazon legs in pullets as well.
The girl combs will stay small and yellow, with no more than a peachy tinge, which can increase in tone with activity, until point of lay. Sometimes they have a bit of precocious comb size, but the color is very important. If you've got substantial comb at 6 weeks with true blush pink to pink-red, it will be male.
If red bars come into the wings, that will almost always be male. (You have to recognize true red bars vs. some brick patterning that is transitional that I've had some mixed breed girls get).
Feather sexing is not possible unless you have specific lines that are bred so that the females feather faster than the males. I have some females feather slow and some males feather quickly in different breeds. True feather sexing can only be done as a newly hatched chick (I think within the first 3 days) from lines bred for that quality.
Most importantly among chicks, compare same breed line to same breed line. Different breeds mature differently and even lines within the breeds which makes sexing chicks from the feed store tricky as they commercial lines have a lot of different input in them...and chances are you also get chicks from different batches and thus usually different ages.
There are some general guide lines with wild type (chipmunk colored) chicks.
Usually, tri-color stripes that go from top of the head, down the neck, all the way to the tail is female. Male wild type will have two colors, usually paler on the head, break at the neck, and begin at the back to tail....but that is a generality.
Barred Rocks are purported to be sexable, but the tricks there only work within the same carefully controlled line as the leg wash and head dot shape vary between the sexes between lines. Commercial quality is extremely unreliable with the traditional BR chick sexing. (ie if black leg wash on front of yellow legs and small defined head dot, female).
Of course if you get the sexable chicks either from the auto-sexing breeds, [Welsummer (from good lines), Cream Legbar, Rhodebar, etc,] or sex-links (Red and Black), you know from color down at hatch which is which...and that does make life nice.
HTH
LofMc
