I got three straight run Buff Orps a year ago. Of course, all cockerels. Two became very aggressive at 4 months when hormones hit, both to me and the pullets. They were culled soon after.Orps are also supposed to be very mellow and more docile.
The third guy is ok with the girls, but oft times "forgets" I'm the boss. I now take a big stick into the run when I go in. Sometimes he's fine, sometimes he isn't. The stick forces him back until he "remembers" who's in charge.