Where do your drum mixes peak (Pre-Master)?

I'm going to assume you mean in the digital world in which case they can peak pretty high, usually a mix will peak out during snare or kick hits and then they get squashed down via clipping or whatever during mastering, but there's really no right number. -6 to -10db for a whole drum mix is probably ok?
 
I usually go with the whole mix peaking at -6db. So drum mix is peaking somewhere around -10db.